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• Setting up a VPN connection to Amazon VPC - routing

  - by Keeno

  I am having some real issues setting up a VPN between out office and AWS VPC. The "tunnels" appear to be up, however I don't know if they are configured correctly. The device I am using is a Netgear VPN Firewall - FVS336GV2 If you see in the attached config downloaded from VPC (#3 Tunnel Interface Configuration), it gives me some "inside" addresses for the tunnel. When setting up the IPsec tunnels do I use the inside tunnel IP's (e.g. 169.254.254.2/30) or do I use my internal network subnet (10.1.1.0/24) I have tried both, when I tried the local network (10.1.1.x) the tracert stops at the router. When I tried with the "inside" ips, the tracert to the amazon VPC (10.0.0.x) goes out over the internet. this all leads me to the next question, for this router, how do I set up stage #4, the static next hop? What are these seemingly random "inside" addresses and where did amazon generate them from? 169.254.254.x seems odd? With a device like this, is the VPN behind the firewall? I have tweaked any IP addresses below so that they are not "real". I am fully aware, this is probably badly worded. Please if there is any further info/screenshots that will help, let me know. Amazon Web Services Virtual Private Cloud IPSec Tunnel #1 ================================================================================ #1: Internet Key Exchange Configuration Configure the IKE SA as follows - Authentication Method : Pre-Shared Key - Pre-Shared Key : --- - Authentication Algorithm : sha1 - Encryption Algorithm : aes-128-cbc - Lifetime : 28800 seconds - Phase 1 Negotiation Mode : main - Perfect Forward Secrecy : Diffie-Hellman Group 2 #2: IPSec Configuration Configure the IPSec SA as follows: - Protocol : esp - Authentication Algorithm : hmac-sha1-96 - Encryption Algorithm : aes-128-cbc - Lifetime : 3600 seconds - Mode : tunnel - Perfect Forward Secrecy : Diffie-Hellman Group 2 IPSec Dead Peer Detection (DPD) will be enabled on the AWS Endpoint. We recommend configuring DPD on your endpoint as follows: - DPD Interval : 10 - DPD Retries : 3 IPSec ESP (Encapsulating Security Payload) inserts additional headers to transmit packets. These headers require additional space, which reduces the amount of space available to transmit application data. To limit the impact of this behavior, we recommend the following configuration on your Customer Gateway: - TCP MSS Adjustment : 1387 bytes - Clear Don't Fragment Bit : enabled - Fragmentation : Before encryption #3: Tunnel Interface Configuration Your Customer Gateway must be configured with a tunnel interface that is associated with the IPSec tunnel. All traffic transmitted to the tunnel interface is encrypted and transmitted to the Virtual Private Gateway. The Customer Gateway and Virtual Private Gateway each have two addresses that relate to this IPSec tunnel. Each contains an outside address, upon which encrypted traffic is exchanged. Each also contain an inside address associated with the tunnel interface. The Customer Gateway outside IP address was provided when the Customer Gateway was created. Changing the IP address requires the creation of a new Customer Gateway. The Customer Gateway inside IP address should be configured on your tunnel interface. Outside IP Addresses: - Customer Gateway : 217.33.22.33 - Virtual Private Gateway : 87.222.33.42 Inside IP Addresses - Customer Gateway : 169.254.254.2/30 - Virtual Private Gateway : 169.254.254.1/30 Configure your tunnel to fragment at the optimal size: - Tunnel interface MTU : 1436 bytes #4: Static Routing Configuration: To route traffic between your internal network and your VPC, you will need a static route added to your router. Static Route Configuration Options: - Next hop : 169.254.254.1 You should add static routes towards your internal network on the VGW. The VGW will then send traffic towards your internal network over the tunnels. IPSec Tunnel #2 ================================================================================ #1: Internet Key Exchange Configuration Configure the IKE SA as follows - Authentication Method : Pre-Shared Key - Pre-Shared Key : --- - Authentication Algorithm : sha1 - Encryption Algorithm : aes-128-cbc - Lifetime : 28800 seconds - Phase 1 Negotiation Mode : main - Perfect Forward Secrecy : Diffie-Hellman Group 2 #2: IPSec Configuration Configure the IPSec SA as follows: - Protocol : esp - Authentication Algorithm : hmac-sha1-96 - Encryption Algorithm : aes-128-cbc - Lifetime : 3600 seconds - Mode : tunnel - Perfect Forward Secrecy : Diffie-Hellman Group 2 IPSec Dead Peer Detection (DPD) will be enabled on the AWS Endpoint. We recommend configuring DPD on your endpoint as follows: - DPD Interval : 10 - DPD Retries : 3 IPSec ESP (Encapsulating Security Payload) inserts additional headers to transmit packets. These headers require additional space, which reduces the amount of space available to transmit application data. To limit the impact of this behavior, we recommend the following configuration on your Customer Gateway: - TCP MSS Adjustment : 1387 bytes - Clear Don't Fragment Bit : enabled - Fragmentation : Before encryption #3: Tunnel Interface Configuration Outside IP Addresses: - Customer Gateway : 217.33.22.33 - Virtual Private Gateway : 87.222.33.46 Inside IP Addresses - Customer Gateway : 169.254.254.6/30 - Virtual Private Gateway : 169.254.254.5/30 Configure your tunnel to fragment at the optimal size: - Tunnel interface MTU : 1436 bytes #4: Static Routing Configuration: Static Route Configuration Options: - Next hop : 169.254.254.5 You should add static routes towards your internal network on the VGW. The VGW will then send traffic towards your internal network over the tunnels. EDIT #1 After writing this post, I continued to fiddle and something started to work, just not very reliably. The local IPs to use when setting up the tunnels where indeed my network subnets. Which further confuses me over what these "inside" IP addresses are for. The problem is, results are not consistent what so ever. I can "sometimes" ping, I can "sometimes" RDP using the VPN. Sometimes, Tunnel 1 or Tunnel 2 can be up or down. When I came back into work today, Tunnel 1 was down, so I deleted it and re-created it from scratch. Now I cant ping anything, but Amazon AND the router are telling me tunnel 1/2 are fine. I guess the router/vpn hardware I have just isnt up to the job..... EDIT #2 Now Tunnel 1 is up, Tunnel 2 is down (I didn't change any settings) and I can ping/rdp again. EDIT #3 Screenshot of route table that the router has built up. Current state (tunnel 1 still up and going string, 2 is still down and wont re-connect)

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• How to disable Mac OS X from using swap when there still is "Inactive" memory?

  - by Motin

  A common phenomena in my day to day usage (and several other's according to various posts throughout the internet) of OS X, the system seems to become slow whenever there is no more "Free" memory available. Supposedly, this is due to swapping, since heavy disk activity is apparent and that vm_stat reports many pageouts. (Correct me from wrong) However, the amount of "Inactive" ram is typically around 12.5%-25% of all available memory (^1.) when swapping starts/occurs/ends. According to http://support.apple.com/kb/ht1342 : Inactive memory This information in memory is not actively being used, but was recently used. For example, if you've been using Mail and then quit it, the RAM that Mail was using is marked as Inactive memory. This Inactive memory is available for use by another application, just like Free memory. However, if you open Mail before its Inactive memory is used by a different application, Mail will open quicker because its Inactive memory is converted to Active memory, instead of loading Mail from the slower hard disk. And according to http://developer.apple.com/library/mac/#documentation/Performance/Conceptual/ManagingMemory/Articles/AboutMemory.html : The inactive list contains pages that are currently resident in physical memory but have not been accessed recently. These pages contain valid data but may be released from memory at any time. So, basically: When a program has quit, it's memory becomes marked as Inactive and should be claimable at any time. Still, OS X will prefer to start swapping out memory to the Swap file instead of just claiming this memory, whenever the "Free" memory gets to low. Why? What is the advantage of this behavior over, say, instantly releasing Inactive memory and not even touch the swap file? Some sources (^2.) indicate that OS X would page out the "Inactive" memory to swap before releasing it, but that doesn't make sense now does it if the memory may be released from memory at any time? Swapping is expensive, releasing is cheap, right? Can this behavior be changed using some preference or known hack? (Preferably one that doesn't include disabling swap/dynamic_pager altogether and restarting...) I do appreciate the purge command, as well as the concept of Repairing disk permissions to force some Free memory, but those are ways to painfully force more Free memory than to actually fixing the swap/release decision logic... Btw a similar question was asked here: http://forums.macnn.com/90/mac-os-x/434650/why-does-os-x-swap-when/ and here: http://hintsforums.macworld.com/showthread.php?t=87688 but even though the OPs re-asked the core question, none of the replies addresses an answer to it... ^1. UPDATE 17-mar-2012 Since I first posted this question, I have gone from 4gb to 8gb of installed ram, and the problem remains. The amount of "Inactive" ram was 0.5gb-1.0gb before and is now typically around 1.0-2.0GB when swapping starts/occurs/ends, ie it seems that around 12.5%-25% of the ram is preserved as Inactive by osx kernel logic. ^2. For instance http://apple.stackexchange.com/questions/4288/what-does-it-mean-if-i-have-lots-of-inactive-memory-at-the-end-of-a-work-day : Once all your memory is used (free memory is 0), the OS will write out inactive memory to the swapfile to make more room in active memory. UPDATE 17-mar-2012 Here is a round-up of the methods that have been suggested to help so far: The purge command "Used to approximate initial boot conditions with a cold disk buffer cache for performance analysis. It does not affect anonymous memory that has been allocated through malloc, vm_allocate, etc". This is useful to prevent osx to swap-out the disk cache (which is ridiculous that osx actually does so in the first place), but with the downside that the disk cache is released, meaning that if the disk cache was not about to be swapped out, one would simply end up with a cold disk buffer cache, probably affecting performance negatively. The FreeMemory app and/or Repairing disk permissions to force some Free memory Doesn't help releasing any memory, only moving some gigabytes of memory contents from ram to the hd. In the end, this causes lots of swap-ins when I attempt to use the applications that were open while freeing memory, as a lot of its vm is now on swap. Speeding up swap-allocation using dynamicpagerwrapper Seems a good thing to do in order to speed up swap-usage, but does not address the problem of osx swapping in the first place while there is still inactive memory. Disabling swap by disabling dynamicpager and restarting This will force osx not to use swap to the price of the system hanging when all memory is used. Not a viable alternative... Disabling swap using a hacked dynamicpager Similar to disabling dynamicpager above, some excerpts from the comments to the blog post indicate that this is not a viable solution: "The Inactive Memory is high as usual". "when your system is running out of memory, the whole os hangs...", "if you consume the whole amount of memory of the mac, the machine will likely hang" To sum up, I am still unaware of a way of disabling Mac OS X from using swap when there still is "Inactive" memory. If it isn't possible, maybe at least there is an explanation somewhere of why osx prefers to swap out memory that may be released from memory at any time?

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• How to relink user folders in Windows 7

  - by Jonathan

  The short story: Win7 lost track of my user folders location (desktop, my documents, my pictures etc...). They now reside on a different partition. How can I relink these folders? The long story: The way I partition my drives is: C: - SSD drive for Windows and Program Files D: - A large regular hard drive for all my user data The first thing I do after a fresh Win7 install is move my user folders to D:, by right clicking on these folders under C:\users\username\, choosing the Location tab and clicking on Move. I've just completed encryption of D: using TrueCrypt. It shows a lot of warnings before the encryption process, but (hrrmm...) it does not mention the fact that after encryption the data is located on a new drive letter, say E: This broke Win7's links to my special user folders. How can I relink these folders?

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• Setting up Kerberos SSO in Windows 2008 network

  - by Arturs Licis

  We recently introduced Kerberos (SPNEGO) Single Sign-on in our web-portal, and tested it on a Windows network with Windows 2003 domain controller. Now, trying to test it on Windows 2008 R2 controlled network, SSO just doesn't work due to defective tokens. Up to the moment I was pretty sure that there's something wrong about environment and that were NTLM tokens. We double checked IE settings etc, but nothing helped. Then we checked the following settings for both users (logged on a client test-machine, and the one used as a Service Principal): This account supports Kerberos AES 128 bit encryption. This account supports Kerberos AES 256 bit encryption. .. and error message changed to ' GSSException: Failure unspecified at GSS-API level (Mechanism level: Encryption type AES256CTS mode with HMAC SHA1-96 is not supported/enabled) It makes me think that Internet Explorer receives Kerberos tokens at all times, and there's just some configuration missing, or it was ktpass.exe to be incorrectly executed. Here's how ktpass.exe was invoked: C:ktpass /out portal1.keytab /mapuser USER /princ HTTP/[email protected] /pass *

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• What's up with LDoms: Part 1 - Introduction & Basic Concepts

  - by Stefan Hinker

  LDoms - the correct name is Oracle VM Server for SPARC - have been around for quite a while now.  But to my surprise, I get more and more requests to explain how they work or to give advise on how to make good use of them.  This made me think that writing up a few articles discussing the different features would be a good idea.  Now - I don't intend to rewrite the LDoms Admin Guide or to copy and reformat the (hopefully) well known "Beginners Guide to LDoms" by Tony Shoumack from 2007.  Those documents are very recommendable - especially the Beginners Guide, although based on LDoms 1.0, is still a good place to begin with.  However, LDoms have come a long way since then, and I hope to contribute to their adoption by discussing how they work and what features there are today.  In this and the following posts, I will use the term "LDoms" as a common abbreviation for Oracle VM Server for SPARC, just because it's a lot shorter and easier to type (and presumably, read). So, just to get everyone on the same baseline, lets briefly discuss the basic concepts of virtualization with LDoms.  LDoms make use of a hypervisor as a layer of abstraction between real, physical hardware and virtual hardware.  This virtual hardware is then used to create a number of guest systems which each behave very similar to a system running on bare metal:  Each has its own OBP, each will install its own copy of the Solaris OS and each will see a certain amount of CPU, memory, disk and network resources available to it.  Unlike some other type 1 hypervisors running on x86 hardware, the SPARC hypervisor is embedded in the system firmware and makes use both of supporting functions in the sun4v SPARC instruction set as well as the overall CPU architecture to fulfill its function. The CMT architecture of the supporting CPUs (T1 through T4) provide a large number of cores and threads to the OS.  For example, the current T4 CPU has eight cores, each running 8 threads, for a total of 64 threads per socket.  To the OS, this looks like 64 CPUs.  The SPARC hypervisor, when creating guest systems, simply assigns a certain number of these threads exclusively to one guest, thus avoiding the overhead of having to schedule OS threads to CPUs, as do typical x86 hypervisors.  The hypervisor only assigns CPUs and then steps aside.  It is not involved in the actual work being dispatched from the OS to the CPU, all it does is maintain isolation between different guests. Likewise, memory is assigned exclusively to individual guests.  Here,  the hypervisor provides generic mappings between the physical hardware addresses and the guest's views on memory.  Again, the hypervisor is not involved in the actual memory access, it only maintains isolation between guests. During the inital setup of a system with LDoms, you start with one special domain, called the Control Domain.  Initially, this domain owns all the hardware available in the system, including all CPUs, all RAM and all IO resources.  If you'd be running the system un-virtualized, this would be what you'd be working with.  To allow for guests, you first resize this initial domain (also called a primary domain in LDoms speak), assigning it a small amount of CPU and memory.  This frees up most of the available CPU and memory resources for guest domains.  IO is a little more complex, but very straightforward.  When LDoms 1.0 first came out, the only way to provide IO to guest systems was to create virtual disk and network services and attach guests to these services.  In the meantime, several different ways to connect guest domains to IO have been developed, the most recent one being SR-IOV support for network devices released in version 2.2 of Oracle VM Server for SPARC. I will cover these more advanced features in detail later.  For now, lets have a short look at the initial way IO was virtualized in LDoms: For virtualized IO, you create two services, one "Virtual Disk Service" or vds, and one "Virtual Switch" or vswitch.  You can, of course, also create more of these, but that's more advanced than I want to cover in this introduction.  These IO services now connect real, physical IO resources like a disk LUN or a networt port to the virtual devices that are assigned to guest domains.  For disk IO, the normal case would be to connect a physical LUN (or some other storage option that I'll discuss later) to one specific guest.  That guest would be assigned a virtual disk, which would appear to be just like a real LUN to the guest, while the IO is actually routed through the virtual disk service down to the physical device.  For network, the vswitch acts very much like a real, physical ethernet switch - you connect one physical port to it for outside connectivity and define one or more connections per guest, just like you would plug cables between a real switch and a real system. For completeness, there is another service that provides console access to guest domains which mimics the behavior of serial terminal servers. The connections between the virtual devices on the guest's side and the virtual IO services in the primary domain are created by the hypervisor.  It uses so called "Logical Domain Channels" or LDCs to create point-to-point connections between all of these devices and services.  These LDCs work very similar to high speed serial connections and are configured automatically whenever the Control Domain adds or removes virtual IO. To see all this in action, now lets look at a first example.  I will start with a newly installed machine and configure the control domain so that it's ready to create guest systems. In a first step, after we've installed the software, let's start the virtual console service and downsize the primary domain.  root@sun # ldm list NAME STATE FLAGS CONS VCPU MEMORY UTIL UPTIME primary active -n-c-- UART 512 261632M 0.3% 2d 13h 58m root@sun # ldm add-vconscon port-range=5000-5100 \ primary-console primary root@sun # svcadm enable vntsd root@sun # svcs vntsd STATE STIME FMRI online 9:53:21 svc:/ldoms/vntsd:default root@sun # ldm set-vcpu 16 primary root@sun # ldm set-mau 1 primary root@sun # ldm start-reconf primary root@sun # ldm set-memory 7680m primary root@sun # ldm add-config initial root@sun # shutdown -y -g0 -i6 So what have I done: I've defined a range of ports (5000-5100) for the virtual network terminal service and then started that service.  The vnts will later provide console connections to guest systems, very much like serial NTS's do in the physical world. Next, I assigned 16 vCPUs (on this platform, a T3-4, that's two cores) to the primary domain, freeing the rest up for future guest systems.  I also assigned one MAU to this domain.  A MAU is a crypto unit in the T3 CPU.  These need to be explicitly assigned to domains, just like CPU or memory.  (This is no longer the case with T4 systems, where crypto is always available everywhere.) Before I reassigned the memory, I started what's called a "delayed reconfiguration" session.  That avoids actually doing the change right away, which would take a considerable amount of time in this case.  Instead, I'll need to reboot once I'm all done.  I've assigned 7680MB of RAM to the primary.  That's 8GB less the 512MB which the hypervisor uses for it's own private purposes.  You can, depending on your needs, work with less.  I'll spend a dedicated article on sizing, discussing the pros and cons in detail. Finally, just before the reboot, I saved my work on the ILOM, to make this configuration available after a powercycle of the box.  (It'll always be available after a simple reboot, but the ILOM needs to know the configuration of the hypervisor after a power-cycle, before the primary domain is booted.) Now, lets create a first disk service and a first virtual switch which is connected to the physical network device igb2. We will later use these to connect virtual disks and virtual network ports of our guest systems to real world storage and network. root@sun # ldm add-vds primary-vds root@sun # ldm add-vswitch net-dev=igb2 switch-primary primary You are free to choose whatever names you like for the virtual disk service and the virtual switch.  I strongly recommend that you choose names that make sense to you and describe the function of each service in the context of your implementation.  For the vswitch, for example, you could choose names like "admin-vswitch" or "production-network" etc. This already concludes the configuration of the control domain.  We've freed up considerable amounts of CPU and RAM for guest systems and created the necessary infrastructure - console, vts and vswitch - so that guests systems can actually interact with the outside world.  The system is now ready to create guests, which I'll describe in the next section. For further reading, here are some recommendable links: The LDoms 2.2 Admin Guide The "Beginners Guide to LDoms" The LDoms Information Center on MOS LDoms on OTN

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• Commit in SQL

  - by PRajkumar

  SQL Transaction Control Language Commands (TCL)                                           (COMMIT) Commit Transaction As a SQL language we use transaction control language very frequently. Committing a transaction means making permanent the changes performed by the SQL statements within the transaction. A transaction is a sequence of SQL statements that Oracle Database treats as a single unit. This statement also erases all save points in the transaction and releases transaction locks. Oracle Database issues an implicit COMMIT before and after any data definition language (DDL) statement. Oracle recommends that you explicitly end every transaction in your application programs with a COMMIT or ROLLBACK statement, including the last transaction, before disconnecting from Oracle Database. If you do not explicitly commit the transaction and the program terminates abnormally, then the last uncommitted transaction is automatically rolled back.   Until you commit a transaction: ·         You can see any changes you have made during the transaction by querying the modified tables, but other users cannot see the changes. After you commit the transaction, the changes are visible to other users' statements that execute after the commit ·         You can roll back (undo) any changes made during the transaction with the ROLLBACK statement   Note: Most of the people think that when we type commit data or changes of what you have made has been written to data files, but this is wrong when you type commit it means that you are saying that your job has been completed and respective verification will be done by oracle engine that means it checks whether your transaction achieved consistency when it finds ok it sends a commit message to the user from log buffer but not from data buffer, so after writing data in log buffer it insists data buffer to write data in to data files, this is how it works.   Before a transaction that modifies data is committed, the following has occurred: ·         Oracle has generated undo information. The undo information contains the old data values changed by the SQL statements of the transaction ·         Oracle has generated redo log entries in the redo log buffer of the System Global Area (SGA). The redo log record contains the change to the data block and the change to the rollback block. These changes may go to disk before a transaction is committed ·         The changes have been made to the database buffers of the SGA. These changes may go to disk before a transaction is committed   Note:   The data changes for a committed transaction, stored in the database buffers of the SGA, are not necessarily written immediately to the data files by the database writer (DBWn) background process. This writing takes place when it is most efficient for the database to do so. It can happen before the transaction commits or, alternatively, it can happen some times after the transaction commits.   When a transaction is committed, the following occurs: 1.      The internal transaction table for the associated undo table space records that the transaction has committed, and the corresponding unique system change number (SCN) of the transaction is assigned and recorded in the table 2.      The log writer process (LGWR) writes redo log entries in the SGA's redo log buffers to the redo log file. It also writes the transaction's SCN to the redo log file. This atomic event constitutes the commit of the transaction 3.      Oracle releases locks held on rows and tables 4.      Oracle marks the transaction complete   Note:   The default behavior is for LGWR to write redo to the online redo log files synchronously and for transactions to wait for the redo to go to disk before returning a commit to the user. However, for lower transaction commit latency application developers can specify that redo be written asynchronously and that transaction do not need to wait for the redo to be on disk.   The syntax of Commit Statement is   COMMIT [WORK] [COMMENT ‘your comment’]; ·         WORK is optional. The WORK keyword is supported for compliance with standard SQL. The statements COMMIT and COMMIT WORK are equivalent. Examples Committing an Insert INSERT INTO table_name VALUES (val1, val2); COMMIT WORK; ·         COMMENT Comment is also optional. This clause is supported for backward compatibility. Oracle recommends that you used named transactions instead of commit comments. Specify a comment to be associated with the current transaction. The 'text' is a quoted literal of up to 255 bytes that Oracle Database stores in the data dictionary view DBA_2PC_PENDING along with the transaction ID if a distributed transaction becomes in doubt. This comment can help you diagnose the failure of a distributed transaction. Examples The following statement commits the current transaction and associates a comment with it: COMMIT     COMMENT 'In-doubt transaction Code 36, Call (415) 555-2637'; ·         WRITE Clause Use this clause to specify the priority with which the redo information generated by the commit operation is written to the redo log. This clause can improve performance by reducing latency, thus eliminating the wait for an I/O to the redo log. Use this clause to improve response time in environments with stringent response time requirements where the following conditions apply: The volume of update transactions is large, requiring that the redo log be written to disk frequently. The application can tolerate the loss of an asynchronously committed transaction. The latency contributed by waiting for the redo log write to occur contributes significantly to overall response time. You can specify the WAIT | NOWAIT and IMMEDIATE | BATCH clauses in any order. Examples To commit the same insert operation and instruct the database to buffer the change to the redo log, without initiating disk I/O, use the following COMMIT statement: COMMIT WRITE BATCH; Note: If you omit this clause, then the behavior of the commit operation is controlled by the COMMIT_WRITE initialization parameter, if it has been set. The default value of the parameter is the same as the default for this clause. Therefore, if the parameter has not been set and you omit this clause, then commit records are written to disk before control is returned to the user. WAIT | NOWAIT Use these clauses to specify when control returns to the user. The WAIT parameter ensures that the commit will return only after the corresponding redo is persistent in the online redo log. Whether in BATCH or IMMEDIATE mode, when the client receives a successful return from this COMMIT statement, the transaction has been committed to durable media. A crash occurring after a successful write to the log can prevent the success message from returning to the client. In this case the client cannot tell whether or not the transaction committed. The NOWAIT parameter causes the commit to return to the client whether or not the write to the redo log has completed. This behavior can increase transaction throughput. With the WAIT parameter, if the commit message is received, then you can be sure that no data has been lost. Caution: With NOWAIT, a crash occurring after the commit message is received, but before the redo log record(s) are written, can falsely indicate to a transaction that its changes are persistent. If you omit this clause, then the transaction commits with the WAIT behavior. IMMEDIATE | BATCH Use these clauses to specify when the redo is written to the log. The IMMEDIATE parameter causes the log writer process (LGWR) to write the transaction's redo information to the log. This operation option forces a disk I/O, so it can reduce transaction throughput. The BATCH parameter causes the redo to be buffered to the redo log, along with other concurrently executing transactions. When sufficient redo information is collected, a disk write of the redo log is initiated. This behavior is called "group commit", as redo for multiple transactions is written to the log in a single I/O operation. If you omit this clause, then the transaction commits with the IMMEDIATE behavior. ·         FORCE Clause Use this clause to manually commit an in-doubt distributed transaction or a corrupt transaction. ·         In a distributed database system, the FORCE string [, integer] clause lets you manually commit an in-doubt distributed transaction. The transaction is identified by the 'string' containing its local or global transaction ID. To find the IDs of such transactions, query the data dictionary view DBA_2PC_PENDING. You can use integer to specifically assign the transaction a system change number (SCN). If you omit integer, then the transaction is committed using the current SCN. ·         The FORCE CORRUPT_XID 'string' clause lets you manually commit a single corrupt transaction, where string is the ID of the corrupt transaction. Query the V$CORRUPT_XID_LIST data dictionary view to find the transaction IDs of corrupt transactions. You must have DBA privileges to view the V$CORRUPT_XID_LIST and to specify this clause. ·         Specify FORCE CORRUPT_XID_ALL to manually commit all corrupt transactions. You must have DBA privileges to specify this clause. Examples Forcing an in doubt transaction. Example The following statement manually commits a hypothetical in-doubt distributed transaction. Query the V$CORRUPT_XID_LIST data dictionary view to find the transaction IDs of corrupt transactions. You must have DBA privileges to view the V$CORRUPT_XID_LIST and to issue this statement. COMMIT FORCE '22.57.53';

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• How to Make Your Verizon FIOS Router 1000% More Secure

  - by The Geek

  If you’ve just switched to Verizon FIOS and they’ve installed the new router in your house, there’s just one problem: it’s set to use lousy WEP encryption by default, instead of the much more secure WPA2. Here’s how to fix it. The problem with WEP encryption is that it can be cracked really easily—a skilled hacker can do it in a few minutes, and even an unskilled geek can do it in just a little more time with the right tools. Once they’ve done that, they can leech off your internet connection and do anything they want—including illegal stuff coming from your network. Note: if you are using an old Nintendo DS connected to the internet, they usually only support WEP encryption, so you may not want to do this Latest Features How-To Geek ETC The Complete List of iPad Tips, Tricks, and Tutorials The 50 Best Registry Hacks that Make Windows Better The How-To Geek Holiday Gift Guide (Geeky Stuff We Like) LCD? LED? Plasma? The How-To Geek Guide to HDTV Technology The How-To Geek Guide to Learning Photoshop, Part 8: Filters Improve Digital Photography by Calibrating Your Monitor The Spam Police Parts 1 and 2 – Goodbye Spammers [Videos] Snow Angels Theme for Windows 7 Exploring the Jungle Ruins Wallpaper Protect Your Privacy When Browsing with Chrome and Iron Browser Free Shipping Day is Friday, December 17, 2010 – National Free Shipping Day Find an Applicable Quote for Any Programming Situation

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• Oracle's SPARC T4, 007 Style

  - by Kristin Rose

  The names 4, T4, and this power house travels hand in hand with its good friend SPARC. About 6 years ago on-chip encryption acceleration was first shipped in a commercial system, the SPARC T1. Today, thanks to Oracle SPARC innovative leadership in on-chip encryption acceleration, complex cryptographic computations was born and has since rapidly evolved. Customers can now have security with performance because we my friend, are in the Age of Big Data.If you need some high speed action in your life, listen here. The SPARC T4 systems offer customers much more value for applications than just increased performance through its cross sell opportunity. This is done by enabling partners to integrate your own applications to Oracle’s SPARC T4 Servers for Cloud deployments, and providing direct business benefits that supersedes the commodity approach to data center computing such as security, performance and optimization.As companies continue down this complex path of big data, eCommerce, and mobility, the need to provide better and more in-depth security is more prominent than ever. Oracle’s SPARC T4 processor allows customers to deliver the highest levels of application security, as well as deliver the necessary level performance without added cost, and complexity.To learn more behind the value of SPARC T4, check out a more in-depth blog here. For more on the SPARC T4 family of products, click here.Encryption Lives Another Day,The OPN Communications Team Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman","serif";}

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• Anonymous exposes sensitive bank emails

  - by martin.abrahams

  As expected for quite a while, emails purporting to reveal alleged naughtiness at a major bank have been released today. A bank spokesman says "We are confident that his extravagant assertions are untrue". The BBC report concludes…  “Firms are increasingly concerned about the prospect of disgruntled staff taking caches of sensitive e-mails with them when they leave, said Rami Habal, of security firm Proofpoint. "You can't do anything about people copying the content," he said. But firms can put measures in place, such as revoking encryption keys, which means stolen e-mails become unreadable, he added.” Actually, there is something you can do to guard against copying. While traditional encryption lets authorised recipients make unprotected copies long before you revoke the keys, Oracle IRM provides encryption AND guards against unprotected copies being made. Recipients can be authorised to save protected copies, and cut-and-paste within the scope of a protected workflow or email thread – but can be prevented from saving unprotected copies or pasting to unprotected files and emails.  The IRM audit trail would also help track down attempts to open the protected emails and documents by unauthorised individuals within or beyond your perimeter.

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• Ubuntu 12.04 connected to wireless network but internet not working

  - by A.J.

  I can connect to my house's wireless network just fine, but when I'm connected I can't browse the web. Firefox starts connecting to a site and then just poops out. This doesn't happen on my roommates' computers (running Windows) or on our 3DSes, so I know it's just my laptop. I already tried sudo dhclient -r sudo dhclient sudo ifconfig eth0 down sudo ifconfig eth0 up Results of a few commands I was asked to run in comments: ping -c 2 4.2.2.2 PING 4.2.2.2 (4.2.2.2) 56(84) bytes of data. ^C --- 4.2.2.2 ping statistics --- 2 packets transmitted, 0 received, 100% packet loss, time 1007ms ping -c 2 google.com PING google.com (173.194.33.38) 56(84) bytes of data. --- google.com ping statistics --- 2 packets transmitted, 0 received, 100% packet loss, time 1006ms nm-tool NetworkManager Tool State: connected (global) - Device: eth0 ----------------------------------------------------------------- Type: Wired Driver: atl1c State: unavailable Default: no HW Address: 88:AE:1D:6B:4E:E7 Capabilities: Carrier Detect: yes Speed: 100 Mb/s Wired Properties Carrier: off - Device: wlan0 [JUSTICE] ----------------------------------------------------- Type: 802.11 WiFi Driver: ath9k State: connected Default: yes HW Address: 1C:65:9D:65:C6:31 Capabilities: Speed: 1 Mb/s Wireless Properties WEP Encryption: yes WPA Encryption: yes WPA2 Encryption: yes Wireless Access Points (* = current AP) HOME-9B18: Infra, 00:26:F3:53:9B:18, Freq 2412 MHz, Rate 54 Mb/s, Strength 34 WPA WPA2 cougdad48 Network: Infra, 60:33:4B:E4:C4:5D, Freq 2437 MHz, Rate 54 Mb/s, Strength 22 WPA2 cougdad48 Guest Network: Infra, 66:33:4B:E4:C4:5D, Freq 2437 MHz, Rate 54 Mb/s, Strength 20 WPA2 belkin.ade: Infra, 94:44:52:FF:8A:DE, Freq 2457 MHz, Rate 54 Mb/s, Strength 20 WPA WPA2 *JUSTICE: Infra, 00:24:01:7B:9F:7E, Freq 2462 MHz, Rate 54 Mb/s, Strength 88 WEP CenturyLink: Infra, B2:B2:DC:8E:E2:58, Freq 2462 MHz, Rate 54 Mb/s, Strength 17 WPA WPA2 IPv4 Settings: Address: 192.168.0.11 Prefix: 24 (255.255.255.0) Gateway: 192.168.0.1 DNS: 192.168.0.1 (JUSTICE is my home's network.) ping -c 2 198.168.0.1 PING 198.168.0.1 (198.168.0.1) 56(84) bytes of data. --- 198.168.0.1 ping statistics --- 2 packets transmitted, 0 received, 100% packet loss, time 1007ms

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• Can't connect to or see my wifi ssid

  - by ant

  Today I installed ubuntu 12.04 on my laptop. I am unable to see my home SSID or even connect to it. I've tried to connect as a hidden SSID but I always get prompted for authorization although my key is correct. I'm in in Europe but my laptop is from US. I'm not sure if that is relevant. I've read around this site and saw something that has to do with setting the channel above 11. I'm not sure I did that correctly I did this : How to use Wi-Fi channels above 11? Did't help. I'm able to connect with cable but not via wifi either windows or linux. Other devices in my home can connect without any issues, even the kindle. Here is the screenshot from my router : Here is some additional info : lspci | grep -i network 08:00.0 Network controller: Qualcomm Atheros AR9285 Wireless Network Adapter (PCI-Express) (rev 01) lspci -nnk | grep -A2 0280 08:00.0 Network controller [0280]: Qualcomm Atheros AR9285 Wireless Network Adapter (PCI-Express) [168c:002b] (rev 01) Subsystem: Hewlett-Packard Company U98Z062.10 802.11bgn Wireless Half-size Mini PCIe Card [103c:303f] Kernel driver in use: ath9k m-tool NetworkManager Tool State: connected (global) Device: wlan0 ---------------------------------------------------------------- Type: 802.11 WiFi Driver: ath9k State: disconnected Default: no HW Address: 90:4C:E5:38:79:0D Capabilities: Wireless Properties WEP Encryption: yes WPA Encryption: yes WPA2 Encryption: yes I'm not sure what to do next. Any suggestions?

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• SQL SERVER – Introduction to SQL Server 2014 In-Memory OLTP

  - by Pinal Dave

  In SQL Server 2014 Microsoft has introduced a new database engine component called In-Memory OLTP aka project “Hekaton” which is fully integrated into the SQL Server Database Engine. It is optimized for OLTP workloads accessing memory resident data. In-memory OLTP helps us create memory optimized tables which in turn offer significant performance improvement for our typical OLTP workload. The main objective of memory optimized table is to ensure that highly transactional tables could live in memory and remain in memory forever without even losing out a single record. The most significant part is that it still supports majority of our Transact-SQL statement. Transact-SQL stored procedures can be compiled to machine code for further performance improvements on memory-optimized tables. This engine is designed to ensure higher concurrency and minimal blocking. In-Memory OLTP alleviates the issue of locking, using a new type of multi-version optimistic concurrency control. It also substantially reduces waiting for log writes by generating far less log data and needing fewer log writes. Points to remember Memory-optimized tables refer to tables using the new data structures and key words added as part of In-Memory OLTP. Disk-based tables refer to your normal tables which we used to create in SQL Server since its inception. These tables use a fixed size 8 KB pages that need to be read from and written to disk as a unit. Natively compiled stored procedures refer to an object Type which is new and is supported by in-memory OLTP engine which convert it into machine code, which can further improve the data access performance for memory –optimized tables. Natively compiled stored procedures can only reference memory-optimized tables, they can’t be used to reference any disk –based table. Interpreted Transact-SQL stored procedures, which is what SQL Server has always used. Cross-container transactions refer to transactions that reference both memory-optimized tables and disk-based tables. Interop refers to interpreted Transact-SQL that references memory-optimized tables. Using In-Memory OLTP In-Memory OLTP engine has been available as part of SQL Server 2014 since June 2013 CTPs. Installation of In-Memory OLTP is part of the SQL Server setup application. The In-Memory OLTP components can only be installed with a 64-bit edition of SQL Server 2014 hence they are not available with 32-bit editions. Creating Databases Any database that will store memory-optimized tables must have a MEMORY_OPTIMIZED_DATA filegroup. This filegroup is specifically designed to store the checkpoint files needed by SQL Server to recover the memory-optimized tables, and although the syntax for creating the filegroup is almost the same as for creating a regular filestream filegroup, it must also specify the option CONTAINS MEMORY_OPTIMIZED_DATA. Here is an example of a CREATE DATABASE statement for a database that can support memory-optimized tables: CREATE DATABASE InMemoryDB ON PRIMARY(NAME = [InMemoryDB_data], FILENAME = 'D:\data\InMemoryDB_data.mdf', size=500MB), FILEGROUP [SampleDB_mod_fg] CONTAINS MEMORY_OPTIMIZED_DATA (NAME = [InMemoryDB_mod_dir], FILENAME = 'S:\data\InMemoryDB_mod_dir'), (NAME = [InMemoryDB_mod_dir], FILENAME = 'R:\data\InMemoryDB_mod_dir') LOG ON (name = [SampleDB_log], Filename='L:\log\InMemoryDB_log.ldf', size=500MB) COLLATE Latin1_General_100_BIN2; Above example code creates files on three different drives (D:  S: and R:) for the data files and in memory storage so if you would like to run this code kindly change the drive and folder locations as per your convenience. Also notice that binary collation was specified as Windows (non-SQL). BIN2 collation is the only collation support at this point for any indexes on memory optimized tables. It is also possible to add a MEMORY_OPTIMIZED_DATA file group to an existing database, use the below command to achieve the same. ALTER DATABASE AdventureWorks2012 ADD FILEGROUP hekaton_mod CONTAINS MEMORY_OPTIMIZED_DATA; GO ALTER DATABASE AdventureWorks2012 ADD FILE (NAME='hekaton_mod', FILENAME='S:\data\hekaton_mod') TO FILEGROUP hekaton_mod; GO Creating Tables There is no major syntactical difference between creating a disk based table or a memory –optimized table but yes there are a few restrictions and a few new essential extensions. Essentially any memory-optimized table should use the MEMORY_OPTIMIZED = ON clause as shown in the Create Table query example. DURABILITY clause (SCHEMA_AND_DATA or SCHEMA_ONLY) Memory-optimized table should always be defined with a DURABILITY value which can be either SCHEMA_AND_DATA or  SCHEMA_ONLY the former being the default. A memory-optimized table defined with DURABILITY=SCHEMA_ONLY will not persist the data to disk which means the data durability is compromised whereas DURABILITY= SCHEMA_AND_DATA ensures that data is also persisted along with the schema. Indexing Memory Optimized Table A memory-optimized table must always have an index for all tables created with DURABILITY= SCHEMA_AND_DATA and this can be achieved by declaring a PRIMARY KEY Constraint at the time of creating a table. The following example shows a PRIMARY KEY index created as a HASH index, for which a bucket count must also be specified. CREATE TABLE Mem_Table ( [Name] VARCHAR(32) NOT NULL PRIMARY KEY NONCLUSTERED HASH WITH (BUCKET_COUNT = 100000), [City] VARCHAR(32) NULL, [State_Province] VARCHAR(32) NULL, [LastModified] DATETIME NOT NULL, ) WITH (MEMORY_OPTIMIZED = ON, DURABILITY = SCHEMA_AND_DATA); Now as you can see in the above query example we have used the clause MEMORY_OPTIMIZED = ON to make sure that it is considered as a memory optimized table and not just a normal table and also used the DURABILITY Clause= SCHEMA_AND_DATA which means it will persist data along with metadata and also you can notice this table has a PRIMARY KEY mentioned upfront which is also a mandatory clause for memory-optimized tables. We will talk more about HASH Indexes and BUCKET_COUNT in later articles on this topic which will be focusing more on Row and Index storage on Memory-Optimized tables. So stay tuned for that as well. Now as we covered the basics of Memory Optimized tables and understood the key things to remember while using memory optimized tables, let’s explore more using examples to understand the Performance gains using memory-optimized tables. I will be using the database which i created earlier in this article i.e. InMemoryDB in the below Demo Exercise. USE InMemoryDB GO -- Creating a disk based table CREATE TABLE dbo.Disktable ( Id INT IDENTITY, Name CHAR(40) ) GO CREATE NONCLUSTERED INDEX IX_ID ON dbo.Disktable (Id) GO -- Creating a memory optimized table with similar structure and DURABILITY = SCHEMA_AND_DATA CREATE TABLE dbo.Memorytable_durable ( Id INT NOT NULL PRIMARY KEY NONCLUSTERED Hash WITH (bucket_count =1000000), Name CHAR(40) ) WITH (MEMORY_OPTIMIZED = ON, DURABILITY = SCHEMA_AND_DATA) GO -- Creating an another memory optimized table with similar structure but DURABILITY = SCHEMA_Only CREATE TABLE dbo.Memorytable_nondurable ( Id INT NOT NULL PRIMARY KEY NONCLUSTERED Hash WITH (bucket_count =1000000), Name CHAR(40) ) WITH (MEMORY_OPTIMIZED = ON, DURABILITY = SCHEMA_only) GO -- Now insert 100000 records in dbo.Disktable and observe the Time Taken DECLARE @i_t bigint SET @i_t =1 WHILE @i_t<= 100000 BEGIN INSERT INTO dbo.Disktable(Name) VALUES('sachin' + CONVERT(VARCHAR,@i_t)) SET @i_t+=1 END -- Do the same inserts for Memory table dbo.Memorytable_durable and observe the Time Taken DECLARE @i_t bigint SET @i_t =1 WHILE @i_t<= 100000 BEGIN INSERT INTO dbo.Memorytable_durable VALUES(@i_t, 'sachin' + CONVERT(VARCHAR,@i_t)) SET @i_t+=1 END -- Now finally do the same inserts for Memory table dbo.Memorytable_nondurable and observe the Time Taken DECLARE @i_t bigint SET @i_t =1 WHILE @i_t<= 100000 BEGIN INSERT INTO dbo.Memorytable_nondurable VALUES(@i_t, 'sachin' + CONVERT(VARCHAR,@i_t)) SET @i_t+=1 END The above 3 Inserts took 1.20 minutes, 54 secs, and 2 secs respectively to insert 100000 records on my machine with 8 Gb RAM. This proves the point that memory-optimized tables can definitely help businesses achieve better performance for their highly transactional business table and memory- optimized tables with Durability SCHEMA_ONLY is even faster as it does not bother persisting its data to disk which makes it supremely fast. Koenig Solutions is one of the few organizations which offer IT training on SQL Server 2014 and all its updates. Now, I leave the decision on using memory_Optimized tables on you, I hope you like this article and it helped you understand  the fundamentals of IN-Memory OLTP . Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: PostADay, SQL, SQL Authority, SQL Performance, SQL Query, SQL Server, SQL Tips and Tricks, T SQL Tagged: Koenig

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• Finding nuggets in ARC discussions

  - by alanc

  A bit over twenty years ago, Sun formed an Architecture Review Committee (ARC) that evaluates proposals to change interfaces between components in Sun software products. During the OpenSolaris days, we opened many of these discussions to the community. While they’re back behind closed doors, and at a different company now, we still continue to hold these reviews for the software from what’s now the Sun Systems Group division of Oracle. Recently one of these reviews was held (via e-mail discussion) to review a proposal to update our GNU findutils package to the latest upstream release. One of the upstream changes discussed was the addition of an “oldfind” program. In findutils 4.3, find was modified to use the fts() function to walk the directory tree, and oldfind was created to provide the old mechanism in case there were bugs in the new implementation that users needed to workaround. In Solaris 11 though, we still ship the find descended from SVR4 as /usr/bin/find and the GNU find is available as either /usr/bin/gfind or /usr/gnu/bin/find. This raised the discussion of if we should add oldfind, and if so what should we call it. Normally our policy is to only add the g* names for GNU commands that conflict with an existing Solaris command – for instance, we ship /usr/bin/emacs, not /usr/bin/gemacs. In this case however, that seemed like it would be more confusing to have /usr/bin/oldfind be the older version of /usr/bin/gfind not of /usr/bin/find. Thus if we shipped it, it would make more sense to call it /usr/bin/goldfind, which several ARC members noted read more naturally as “gold find” than as “g old find”. One of the concerns we often discuss in ARC is if a change is likely to be understood by users or if it will result in more calls to support. As we hit this part of the discussion on a Friday at the end of a long week, I couldn’t resist putting forth a hypothetical support call for this command: “Hello, Oracle Solaris Support, how may I help you?” “My admin is out sick, but he sent an email that he put the findutils package on our server, and I can run goldfind now. I tried it, but goldfind didn’t find gold.” “Did he get the binutils package too?” “No he just said findutils, do we need binutils?” “Well, gold comes in the binutils package, so goldfind would be able to find gold if you got that package.” “How much does Oracle charge for that package?” “It’s free for Solaris users.” “You mean Oracle ships packages of gold to customers for free?” “Yes, if you get the binutils package, it includes GNU gold.” “New gold? Is that some sort of alchemy, turning stuff into gold?” “Not new gold, gold from the GNU project.” “Oracle’s taking gold from the GNU project and shipping it to me?” “Yes, if you get binutils, that package includes gold along with the other tools from the GNU project.” “And GNU doesn’t mind Oracle taking their gold and giving it to customers?” “No, GNU is a non-profit whose goal is to share their software.” “Sharing software sure, but gold? Where does a non-profit like GNU get gold anyway?” “Oh, Google donated it to them.” “Ah! So Oracle will give me the gold that GNU got from Google!” “Yes, if you get the package from us.” “How do I get the package with the gold?” “Just run pkg install binutils and it will put it on your disk.” “We’ve got multiple disks here - which one will it put it on?” “The one with the system image - do you know which one that is? “Well the note from the admin says the system is on the first disk and the users are on the second disk.” “Okay, so it should go on the first disk then.” “And where will I find the gold?” “It will be in the /usr/bin directory.” “In the user’s bin? So thats on the second disk?” “No, it would be on the system disk, with the other development tools, like make, as, and what.” “So what’s on the first disk?” “Well if the system image is there the commands should all be there.” “All the commands? Not just what?” “Right, all the commands that come with the OS, like the shell, ps, and who.” “So who’s on the first disk too?” “Yes. Did your admin say when he’d be back?” “No, just that he had a massive headache and was going home after I tried to get him to explain this stuff to me.” “I can’t imagine why.” “Oh, is why a command too?” “No, _why was a Ruby programmer.” “Ruby? Do you give those away with the gold too?” “Yes, but it comes in the ruby package, not binutils.” “Oh, I’ll have to have my admin get that package too! Thanks!” Needless to say, we decided this might not be the best idea. Since the GNU package hasn’t had to release a serious bug fix in the new find in the past few years, the new GNU find seems pretty stable, and we always have the SVR4 find to use as a fallback in Solaris, so it didn’t seem that adding oldfind was really necessary, so we passed on including it when we update to the new findutils release. [Apologies to Abbott, Costello, their fans, and everyone who read this far. The Gold (linker) page on Wikipedia may explain some of the above, but can’t explain why goldfind is the old GNU find, but gold is the new GNU ld.]

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• Availability Best Practices on Oracle VM Server for SPARC

  - by jsavit

  This is the first of a series of blog posts on configuring Oracle VM Server for SPARC (also called Logical Domains) for availability. This series will show how to how to plan for availability, improve serviceability, avoid single points of failure, and provide resiliency against hardware and software failures. Availability is a broad topic that has filled entire books, so these posts will focus on aspects specifically related to Oracle VM Server for SPARC. The goal is to improve Reliability, Availability and Serviceability (RAS): An article defining RAS can be found here. Oracle VM Server for SPARC Principles for Availability Let's state some guiding principles for availability that apply to Oracle VM Server for SPARC: Avoid Single Points Of Failure (SPOFs). Systems should be configured so a component failure does not result in a loss of application service. The general method to avoid SPOFs is to provide redundancy so service can continue without interruption if a component fails. For a critical application there may be multiple levels of redundancy so multiple failures can be tolerated. Oracle VM Server for SPARC makes it possible to configure systems that avoid SPOFs. Configure for availability at a level of resource and effort consistent with business needs. Effort and resource should be consistent with business requirements. Production has different availability requirements than test/development, so it's worth expending resources to provide higher availability. Even within the category of production there may be different levels of criticality, outage tolerances, recovery and repair time requirements. Keep in mind that a simple design may be more understandable and effective than a complex design that attempts to "do everything". Design for availability at the appropriate tier or level of the platform stack. Availability can be provided in the application, in the database, or in the virtualization, hardware and network layers they depend on - or using a combination of all of them. It may not be necessary to engineer resilient virtualization for stateless web applications applications where availability is provided by a network load balancer, or for enterprise applications like Oracle Real Application Clusters (RAC) and WebLogic that provide their own resiliency. It's (often) the same architecture whether virtual or not: For example, providing resiliency against a lost device path or failing disk media is done for the same reasons and may use the same design whether in a domain or not. It's (often) the same technique whether using domains or not: Many configuration steps are the same. For example, configuring IPMP or creating a redundant ZFS pool is pretty much the same within the guest whether you're in a guest domain or not. There are configuration steps and choices for provisioning the guest with the virtual network and disk devices, which we will discuss. Sometimes it is different using domains: There are new resources to configure. Most notable is the use of alternate service domains, which provides resiliency in case of a domain failure, and also permits improved serviceability via "rolling upgrades". This is an important differentiator between Oracle VM Server for SPARC and traditional virtual machine environments where all virtual I/O is provided by a monolithic infrastructure that itself is a SPOF. Alternate service domains are widely used to provide resiliency in production logical domains environments. Some things are done via logical domains commands, and some are done in the guest: For example, with Oracle VM Server for SPARC we provide multiple network connections to the guest, and then configure network resiliency in the guest via IP Multi Pathing (IPMP) - essentially the same as for non-virtual systems. On the other hand, we configure virtual disk availability in the virtualization layer, and the guest sees an already-resilient disk without being aware of the details. These blogs will discuss configuration details like this. Live migration is not "high availability" in the sense of "continuous availability": If the server is down, then you don't live migrate from it! (A cluster or VM restart elsewhere would be used). However, live migration can be part of the RAS (Reliability, Availability, Serviceability) picture by improving Serviceability - you can move running domains off of a box before planned service or maintenance. The blog Best Practices - Live Migration on Oracle VM Server for SPARC discusses this. Topics Here are some of the topics that will be covered: Network availability using IP Multipathing and aggregates Disk path availability using virtual disks defined with multipath groups ("mpgroup") Disk media resiliency configuring for redundant disks that can tolerate media loss Multiple service domains - this is probably the most significant item and the one most specific to Oracle VM Server for SPARC. It is very widely deployed in production environments as the means to provide network and disk availability, but it can be confusing. Subsequent articles will describe why and how to configure multiple service domains. Note, for the sake of precision: an I/O domain is any domain that has a physical I/O resource (such as a PCIe bus root complex). A service domain is a domain providing virtual device services to other domains; it is almost always an I/O domain too (so it can have something to serve). Resources Here are some important links; we'll be drawing on their content in the next several articles: Oracle VM Server for SPARC Documentation Maximizing Application Reliability and Availability with SPARC T5 Servers whitepaper by Gary Combs Maximizing Application Reliability and Availability with the SPARC M5-32 Server whitepaper by Gary Combs Summary Oracle VM Server for SPARC offers features that can be used to provide highly-available environments. This and the following blog entries will describe how to plan and deploy them.

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• SQLIO Writes

  - by Grant Fritchey

  SQLIO is a fantastic utility for testing the abilities of the disks in your system. It has a very unfortunate name though, since it's not really a SQL Server testing utility at all. It really is a disk utility. They ought to call it DiskIO because they'd get more people using I think. Anyway, branding is not the point of this blog post. Writes are the point of this blog post. SQLIO works by slamming your disk. It performs as mean reads as it can or it performs as many writes as it can depending on how you've configured your tests. There are much smarter people than me who will get into all the various types of tests you should run. I'd suggest reading a bit of what Jonathan Kehayias (blog|twitter) has to say or wade into Denny Cherry's (blog|twitter) work. They're going to do a better job than I can describing all the benefits and mechanisms around using this excellent piece of software. My concerns are very focused. I needed to set up a series of tests to see how well our product SQL Storage Compress worked. I wanted to know the effects it would have on a system, the disk for sure, but also memory and CPU. How to stress the system? SQLIO of course. But when I set it up and ran it, following the documentation that comes with it, I was seeing better than 99% compression on the files. Don't get me wrong. Our product is magnificent, wonderful, all things great and beautiful, gets you coffee in the morning and is made mostly from bacon. But 99% compression. No, it's not that good. So what's up? Well, it's the configuration. The default mechanism is to load up a file, something large that will overwhelm your disk cache. You're instructed to load the file with a character 0x0. I never got a computer science degree. I went to film school. Because of this, I didn't memorize ASCII tables so when I saw this, I thought it was zero's or something. Nope. It's NULL. That's right, you're making a very large file, but you're filling it with NULL values. That's actually ok when all you're testing is the disk sub-system. But, when you want to test a compression and decompression, that can be an issue. I got around this fairly quickly. Instead of generating a file filled with NULL values, I just copied a database file for my tests. And to test it with SQL Storage Compress, I used a database file that had already been run through compression (about 40% compression on that file if you're interested). Now the reads were taken care of. I am seeing very realistic performance from decompressing the information for reads through SQLIO. But what about writes? Well, the issue is, what does SQLIO write? I don't have access to the code. But I do have access to the results. I did two different tests, just to be sure of what I was seeing. First test, use the .DAT file as described in the documentation. I opened the .DAT file after I was done with SQLIO, using WordPad. Guess what? It's a giant file full of air. SQLIO writes NULL values. What does that do to compression? I did the test again on a copy of an uncompressed database file. Then I ran the original and the SQLIO modified copy through ZIP to see what happened. I got better than 99% compression out of the SQLIO modified file (original file of 624,896kb went to 275,871kb compressed, after SQLIO it went to 608kb compressed). So, what does SQLIO write? It writes air. If you're trying to test it with compression or maybe some other type of file storage mechanism like dedupe, you need to know this because your tests really won't be valid. Should I find some other mechanism for testing? Yeah, if all I'm interested in is establishing performance to my own satisfaction, yes. But, I want to be able to compare my results with other people's results and we all need to be using the same tool in order for that to happen. SQLIO is the common mechanism that most people I know use to establish disk performance behavior. It'd be better if we could get SQLIO to do writes in some other fashion. Oh, and before I go, I get to brag a bit. Measuring IOPS, SQL Storage Compress outperforms my disk alone by about 30%.

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• How to add another OS entry in Wubi grub

  - by Amey Jah

  I am trying to install another linux distro besides ubuntu. However, I want to retain my existing windows based loader. Currently, as per my knowledge, MsDos loads grub which then loads Ubuntu (with loop back trick). Now, I have a new linux distro installed on /dev/sda8 (/boot for new distro) where as /root for that OS is installed on /dev/sda9. I tried following steps 1. Add entry into 40_custom of ubuntu grub 2. update grub But upon booting via that entry, it is not able to load the new OS and shows me blank screen. What could be the problem? Additional data: grub.cfg file of ubuntu menuentry 'Ubuntu' --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-simple-fc296be2-8c59-4f21-a3f8-47c38cd0d537' { gfxmode $linux_gfx_mode insmod gzio insmod ntfs set root='hd0,msdos5' if [ x$feature_platform_search_hint = xy ]; then search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos5 --hint-efi=hd0,msdos5 --hint-baremetal=ahci0,msdos5 01CD7BB998DB0870 else search --no-floppy --fs-uuid --set=root 01CD7BB998DB0870 fi loopback loop0 /ubuntu/disks/root.disk set root=(loop0) linux /boot/vmlinuz-3.5.0-19-generic root=UUID=01CD7BB998DB0870 loop=/ubuntu/disks/root.disk ro quiet splash $vt_handoff initrd /boot/initrd.img-3.5.0-19-generic } submenu 'Advanced options for Ubuntu' $menuentry_id_option 'gnulinux-advanced-fc296be2-8c59-4f21-a3f8-47c38cd0d537' { menuentry 'Ubuntu, with Linux 3.5.0-19-generic' --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-3.5.0-19-generic-advanced-fc296be2-8c59-4f21-a3f8-47c38cd0d537' { gfxmode $linux_gfx_mode insmod gzio insmod ntfs set root='hd0,msdos5' if [ x$feature_platform_search_hint = xy ]; then search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos5 --hint-efi=hd0,msdos5 --hint-baremetal=ahci0,msdos5 01CD7BB998DB0870 else search --no-floppy --fs-uuid --set=root 01CD7BB998DB0870 fi loopback loop0 /ubuntu/disks/root.disk set root=(loop0) echo 'Loading Linux 3.5.0-19-generic ...' linux /boot/vmlinuz-3.5.0-19-generic root=UUID=01CD7BB998DB0870 loop=/ubuntu/disks/root.disk ro quiet splash $vt_handoff echo 'Loading initial ramdisk ...' initrd /boot/initrd.img-3.5.0-19-generic } menuentry 'Ubuntu, with Linux 3.5.0-19-generic (recovery mode)' --class ubuntu --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-3.5.0-19-generic-recovery-fc296be2-8c59-4f21-a3f8-47c38cd0d537' { insmod gzio insmod ntfs set root='hd0,msdos5' if [ x$feature_platform_search_hint = xy ]; then search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos5 --hint-efi=hd0,msdos5 --hint-baremetal=ahci0,msdos5 01CD7BB998DB0870 else search --no-floppy --fs-uuid --set=root 01CD7BB998DB0870 fi loopback loop0 /ubuntu/disks/root.disk set root=(loop0) echo 'Loading Linux 3.5.0-19-generic ...' linux /boot/vmlinuz-3.5.0-19-generic root=UUID=01CD7BB998DB0870 loop=/ubuntu/disks/root.disk ro recovery nomodeset echo 'Loading initial ramdisk ...' initrd /boot/initrd.img-3.5.0-19-generic } } ### END /etc/grub.d/10_lupin ### menuentry 'Linux, with Linux core repo kernel' --class arch --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-core repo kernel-true-0f490b6c-e92d-42f0-88e1-0bd3c0d27641'{ load_video set gfxpayload=keep insmod gzio insmod part_msdos insmod ext2 set root='hd0,msdos8' if [ x$feature_platform_search_hint = xy ]; then search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos8 --hint-efi=hd0,msdos8 --hint-baremetal=ahci0,msdos8 0f490b6c-e92d-42f0-88e1-0bd3c0d27641 else search --no-floppy --fs-uuid --set=root 0f490b6c-e92d-42f0-88e1-0bd3c0d27641 fi echo 'Loading Linux core repo kernel ...' linux /boot/vmlinuz-linux root=UUID=0f490b6c-e92d-42f0-88e1-0bd3c0d27641 ro quiet echo 'Loading initial ramdisk ...' initrd /boot/initramfs-linux.img } menuentry 'Linux, with Linux core repo kernel (Fallback initramfs)' --class arch --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-core repo kernel-fallback-0f490b6c-e92d-42f0-88e1-0bd3c0d27641' { load_video set gfxpayload=keep insmod gzio insmod part_msdos insmod ext2 set root='hd0,msdos8' if [ x$feature_platform_search_hint = xy ]; then search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos8 --hint-efi=hd0,msdos8 --hint-baremetal=ahci0,msdos8 0f490b6c-e92d-42f0-88e1-0bd3c0d27641 else search --no-floppy --fs-uuid --set=root 0f490b6c-e92d-42f0-88e1-0bd3c0d27641 fi echo 'Loading Linux core repo kernel ...' linux /boot/vmlinuz-linux root=UUID=0f490b6c-e92d-42f0-88e1-0bd3c0d27641 ro quiet echo 'Loading initial ramdisk ...' initrd /boot/initramfs-linux-fallback.img } lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sda 8:0 0 931.5G 0 disk +-sda1 8:1 0 39.2M 0 part +-sda2 8:2 0 19.8G 0 part +-sda3 8:3 0 205.1G 0 part +-sda4 8:4 0 1K 0 part +-sda5 8:5 0 333.7G 0 part /host +-sda6 8:6 0 233.4G 0 part +-sda7 8:7 0 100.4G 0 part +-sda8 8:8 0 100M 0 part +-sda9 8:9 0 14.7G 0 part +-sda10 8:10 0 21.4G 0 part +-sda11 8:11 0 3G 0 part sr0 11:0 1 1024M 0 rom loop0 7:0 0 29G 0 loop / blkid /dev/loop0: UUID="fc296be2-8c59-4f21-a3f8-47c38cd0d537" TYPE="ext4" /dev/sda1: SEC_TYPE="msdos" LABEL="DellUtility" UUID="5450-4444" TYPE="vfat" /dev/sda2: LABEL="RECOVERY" UUID="78C4FAC1C4FA80A4" TYPE="ntfs" /dev/sda3: LABEL="OS" UUID="DACEFCF1CEFCC6B3" TYPE="ntfs" /dev/sda5: UUID="01CD7BB998DB0870" TYPE="ntfs" /dev/sda6: UUID="01CD7BB99CA3F750" TYPE="ntfs" /dev/sda7: LABEL="Windows 8" UUID="01CDBFB52F925F40" TYPE="ntfs" /dev/sda8: UUID="cdbb5770-d29c-401d-850d-ee30a048ca5e" TYPE="ext2" /dev/sda9: UUID="0f490b6c-e92d-42f0-88e1-0bd3c0d27641" TYPE="ext2" /dev/sda10: UUID="2e7682e5-8917-4edc-9bf9-044fea2ad738" TYPE="ext2" /dev/sda11: UUID="6081da70-d622-42b9-b489-309f922b284e" TYPE="swap Any help is appreciated. Please let me know if you need any extra data.

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• PC hangs and reboots from time to time

  - by Bevor

  Hello, I have a very strange problem: Since I have my new PC, I have always had problems with it. From time to time the computer freezes for some seconds and suddendly reboots by itself. I've had this problem since Ubuntu 9.10. The same with 10.04 and 10.10. That's why I don't think it's a software failure because the problem persist too long. It doesn't have anything to do with what I'm doing at this time. Sometimes I listen to music, sometimes I only use Firefox, sometimes I'm running 2 or 3 VMs, sometimes I watch DVD. So it's not isolatable. I could freeze once a day or once a week. I put the PC to the vendor twice(!). The first time they changed my power supply but the problem persisted. The second time they told me that they made some heavy performance tests 50 hours long but they didn't find anything. (How can that be that I have daily freezes with normal usage). The vendor didn't check the hard discs because they used their own disc with Windows. (So they never checked the Linux installation). Yesterday I made some intensive hard disc scans with "SMART" but no errors were found. I ran memtest for 3 times but no errors found. I already had this problem in my old flat, so I doubt that I has something to do with current fluctuation. I already tried another electrical socket and changed to connector strip but the problem persists. At the moment I removed 2 of the RAMs (2x 2GB). In all I have 6GB, 2x2GB and 2x1GB. Could this difference maybe be a problem? Here is a list of my components. I hope that anybody find something I didn't think about yet. And here a list of my components: 1x AMD Phenom II X4 965 Black Edition, 3,4Ghz, Quad Core, S-AM3, Boxed 2x DDR3-RAM 2048MB, PC3-1333 Mhz, CL9, Kingston ValueRAM 2x DDR3-RAM 1024MB, PC3-1333 Mhz, CL9, Kingston ValueRAM 2x SATA II Seagate Barracuda 7200.12, 1TB 32MB Cache = RAID 1 1x DVD ROM SATA LG DH16NSR, 16x/52x 1x DVD-+R/-+RW SATA LG GH-22NS50 1x Cardreader 18in1 1x PCI-E 2.0 GeForce GTS 250, Retail, 1024MB 1x Power Supply ATX 400 Watt, CHIEFTEC APS-400S, 80 Plus 1x Network card PCI Intel PRO/1000GT 10/100/1000 MBit 1x Mainboard Socket-AM3 ASUS M4A79XTD EVO, ATX lshw: description: Desktop Computer product: System Product Name vendor: System manufacturer version: System Version serial: System Serial Number width: 64 bits capabilities: smbios-2.5 dmi-2.5 vsyscall64 vsyscall32 configuration: boot=normal chassis=desktop uuid=80E4001E-8C00-002C-AA59-E0CB4EBAC29A *-core description: Motherboard product: M4A79XTD EVO vendor: ASUSTeK Computer INC. physical id: 0 version: Rev X.0X serial: MT709CK11101196 slot: To Be Filled By O.E.M. *-firmware description: BIOS vendor: American Megatrends Inc. physical id: 0 version: 0704 (11/25/2009) size: 64KiB capacity: 960KiB capabilities: isa pci pnp apm upgrade shadowing escd cdboot bootselect socketedrom edd int13floppy1200 int13floppy720 int13floppy2880 int5printscreen int9keyboard int14serial int17printer int10video acpi usb ls120boot zipboot biosbootspecification *-cpu description: CPU product: AMD Phenom(tm) II X4 965 Processor vendor: Advanced Micro Devices [AMD] physical id: 4 bus info: cpu@0 version: AMD Phenom(tm) II X4 965 Processor serial: To Be Filled By O.E.M. slot: AM3 size: 800MHz capacity: 3400MHz width: 64 bits clock: 200MHz capabilities: fpu fpu_exception wp vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp x86-64 3dnowext 3dnow constant_tsc rep_good nonstop_tsc extd_apicid pni monitor cx16 popcnt lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs skinit wdt npt lbrv svm_lock nrip_save cpufreq *-cache:0 description: L1 cache physical id: 5 slot: L1-Cache size: 512KiB capacity: 512KiB capabilities: pipeline-burst internal varies data *-cache:1 description: L2 cache physical id: 6 slot: L2-Cache size: 2MiB capacity: 2MiB capabilities: pipeline-burst internal varies unified *-cache:2 description: L3 cache physical id: 7 slot: L3-Cache size: 6MiB capacity: 6MiB capabilities: pipeline-burst internal varies unified *-memory description: System Memory physical id: 36 slot: System board or motherboard size: 2GiB *-bank:0 description: DIMM Synchronous 1333 MHz (0.8 ns) product: ModulePartNumber00 vendor: Manufacturer00 physical id: 0 serial: SerNum00 slot: DIMM0 size: 1GiB width: 64 bits clock: 1333MHz (0.8ns) *-bank:1 description: DIMM Synchronous 1333 MHz (0.8 ns) product: ModulePartNumber01 vendor: Manufacturer01 physical id: 1 serial: SerNum01 slot: DIMM1 size: 1GiB width: 64 bits clock: 1333MHz (0.8ns) *-bank:2 description: DIMM [empty] product: ModulePartNumber02 vendor: Manufacturer02 physical id: 2 serial: SerNum02 slot: DIMM2 *-bank:3 description: DIMM [empty] product: ModulePartNumber03 vendor: Manufacturer03 physical id: 3 serial: SerNum03 slot: DIMM3 *-pci:0 description: Host bridge product: RD780 Northbridge only dual slot PCI-e_GFX and HT1 K8 part vendor: ATI Technologies Inc physical id: 100 bus info: pci@0000:00:00.0 version: 00 width: 32 bits clock: 66MHz *-pci:0 description: PCI bridge product: RD790 PCI to PCI bridge (external gfx0 port A) vendor: ATI Technologies Inc physical id: 2 bus info: pci@0000:00:02.0 version: 00 width: 32 bits clock: 33MHz capabilities: pci pm pciexpress msi ht normal_decode bus_master cap_list configuration: driver=pcieport resources: irq:40 ioport:a000(size=4096) memory:f8000000-fbbfffff ioport:d0000000(size=268435456) *-display description: VGA compatible controller product: G92 [GeForce GTS 250] vendor: nVidia Corporation physical id: 0 bus info: pci@0000:01:00.0 version: a2 width: 64 bits clock: 33MHz capabilities: pm msi pciexpress vga_controller bus_master cap_list rom configuration: driver=nvidia latency=0 resources: irq:18 memory:fa000000-faffffff memory:d0000000-dfffffff memory:f8000000-f9ffffff ioport:ac00(size=128) memory:fbbe0000-fbbfffff *-pci:1 description: PCI bridge product: RD790 PCI to PCI bridge (PCI express gpp port C) vendor: ATI Technologies Inc physical id: 6 bus info: pci@0000:00:06.0 version: 00 width: 32 bits clock: 33MHz capabilities: pci pm pciexpress msi ht normal_decode bus_master cap_list configuration: driver=pcieport resources: irq:41 ioport:b000(size=4096) memory:fbc00000-fbcfffff ioport:f6f00000(size=1048576) *-network description: Ethernet interface product: RTL8111/8168B PCI Express Gigabit Ethernet controller vendor: Realtek Semiconductor Co., Ltd. physical id: 0 bus info: pci@0000:02:00.0 logical name: eth0 version: 03 serial: e0:cb:4e:ba:c2:9a size: 10MB/s capacity: 1GB/s width: 64 bits clock: 33MHz capabilities: pm msi pciexpress msix vpd bus_master cap_list rom ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation configuration: autonegotiation=on broadcast=yes driver=r8169 driverversion=2.3LK-NAPI duplex=half latency=0 link=no multicast=yes port=MII speed=10MB/s resources: irq:45 ioport:b800(size=256) memory:f6fff000-f6ffffff memory:f6ff8000-f6ffbfff memory:fbcf0000-fbcfffff *-pci:2 description: PCI bridge product: RD790 PCI to PCI bridge (PCI express gpp port D) vendor: ATI Technologies Inc physical id: 7 bus info: pci@0000:00:07.0 version: 00 width: 32 bits clock: 33MHz capabilities: pci pm pciexpress msi ht normal_decode bus_master cap_list configuration: driver=pcieport resources: irq:42 ioport:c000(size=4096) memory:fbd00000-fbdfffff *-firewire description: FireWire (IEEE 1394) product: VT6315 Series Firewire Controller vendor: VIA Technologies, Inc. physical id: 0 bus info: pci@0000:03:00.0 version: 00 width: 64 bits clock: 33MHz capabilities: pm msi pciexpress ohci bus_master cap_list configuration: driver=firewire_ohci latency=0 resources: irq:19 memory:fbdff800-fbdfffff ioport:c800(size=256) *-pci:3 description: PCI bridge product: RD790 PCI to PCI bridge (PCI express gpp port E) vendor: ATI Technologies Inc physical id: 9 bus info: pci@0000:00:09.0 version: 00 width: 32 bits clock: 33MHz capabilities: pci pm pciexpress msi ht normal_decode bus_master cap_list configuration: driver=pcieport resources: irq:43 ioport:d000(size=4096) memory:fbe00000-fbefffff *-ide description: IDE interface product: 88SE6121 SATA II Controller vendor: Marvell Technology Group Ltd. physical id: 0 bus info: pci@0000:04:00.0 version: b2 width: 32 bits clock: 33MHz capabilities: ide pm msi pciexpress bus_master cap_list configuration: driver=pata_marvell latency=0 resources: irq:17 ioport:dc00(size=8) ioport:d880(size=4) ioport:d800(size=8) ioport:d480(size=4) ioport:d400(size=16) memory:fbeffc00-fbefffff *-storage description: SATA controller product: SB700/SB800 SATA Controller [IDE mode] vendor: ATI Technologies Inc physical id: 11 bus info: pci@0000:00:11.0 logical name: scsi0 logical name: scsi2 version: 00 width: 32 bits clock: 66MHz capabilities: storage msi ahci_1.0 bus_master cap_list emulated configuration: driver=ahci latency=64 resources: irq:44 ioport:9000(size=8) ioport:8000(size=4) ioport:7000(size=8) ioport:6000(size=4) ioport:5000(size=16) memory:f7fffc00-f7ffffff *-disk:0 description: ATA Disk product: ST31000528AS vendor: Seagate physical id: 0 bus info: scsi@0:0.0.0 logical name: /dev/sda version: CC38 serial: 9VP3WD9Z size: 931GiB (1TB) capabilities: partitioned partitioned:dos configuration: ansiversion=5 signature=000ad206 *-volume:0 UNCLAIMED description: Linux filesystem partition vendor: Linux physical id: 1 bus info: scsi@0:0.0.0,1 version: 1.0 serial: 81839235-21ea-4853-90a4-814779f49000 size: 972MiB capacity: 972MiB capabilities: primary ext2 initialized configuration: filesystem=ext2 modified=2010-12-06 18:32:58 mounted=2010-11-01 07:05:10 state=unknown *-volume:1 UNCLAIMED description: Linux swap volume physical id: 2 bus info: scsi@0:0.0.0,2 version: 1 serial: 22b881d5-6f5c-484d-94e8-e231896fa91b size: 486MiB capacity: 486MiB capabilities: primary nofs swap initialized configuration: filesystem=swap pagesize=4096 *-volume:2 UNCLAIMED description: EXT3 volume vendor: Linux physical id: 3 bus info: scsi@0:0.0.0,3 version: 1.0 serial: ad5b0daf-11e8-4f8f-8598-4e89da9c0d84 size: 47GiB capacity: 47GiB capabilities: primary journaled extended_attributes large_files recover ext3 ext2 initialized configuration: created=2010-02-16 20:42:29 filesystem=ext3 modified=2010-11-29 17:02:34 mounted=2010-12-06 18:32:50 state=clean *-volume:3 UNCLAIMED description: Extended partition physical id: 4 bus info: scsi@0:0.0.0,4 size: 882GiB capacity: 882GiB capabilities: primary extended partitioned partitioned:extended *-logicalvolume UNCLAIMED description: Linux filesystem partition physical id: 5 capacity: 882GiB *-disk:1 description: ATA Disk product: ST31000528AS vendor: Seagate physical id: 1 bus info: scsi@2:0.0.0 logical name: /dev/sdb version: CC38 serial: 9VP3SCPF size: 931GiB (1TB) capabilities: partitioned partitioned:dos configuration: ansiversion=5 signature=000ad206 *-volume:0 UNCLAIMED description: Linux filesystem partition vendor: Linux physical id: 1 bus info: scsi@2:0.0.0,1 version: 1.0 serial: 81839235-21ea-4853-90a4-814779f49000 size: 972MiB capacity: 972MiB capabilities: primary ext2 initialized configuration: filesystem=ext2 modified=2010-12-06 18:32:58 mounted=2010-11-01 07:05:10 state=unknown *-volume:1 UNCLAIMED description: Linux swap volume physical id: 2 bus info: scsi@2:0.0.0,2 version: 1 serial: 22b881d5-6f5c-484d-94e8-e231896fa91b size: 486MiB capacity: 486MiB capabilities: primary nofs swap initialized configuration: filesystem=swap pagesize=4096 *-volume:2 UNCLAIMED description: EXT3 volume vendor: Linux physical id: 3 bus info: scsi@2:0.0.0,3 version: 1.0 serial: ad5b0daf-11e8-4f8f-8598-4e89da9c0d84 size: 47GiB capacity: 47GiB capabilities: primary journaled extended_attributes large_files recover ext3 ext2 initialized configuration: created=2010-02-16 20:42:29 filesystem=ext3 modified=2010-11-29 17:02:34 mounted=2010-12-06 18:32:50 state=clean *-volume:3 UNCLAIMED description: Extended partition physical id: 4 bus info: scsi@2:0.0.0,4 size: 882GiB capacity: 882GiB capabilities: primary extended partitioned partitioned:extended *-logicalvolume UNCLAIMED description: Linux filesystem partition physical id: 5 capacity: 882GiB *-usb:0 description: USB Controller product: SB700/SB800 USB OHCI0 Controller vendor: ATI Technologies Inc physical id: 12 bus info: pci@0000:00:12.0 version: 00 width: 32 bits clock: 66MHz capabilities: ohci bus_master configuration: driver=ohci_hcd latency=64 resources: irq:16 memory:f7ffd000-f7ffdfff *-usb:1 description: USB Controller product: SB700 USB OHCI1 Controller vendor: ATI Technologies Inc physical id: 12.1 bus info: pci@0000:00:12.1 version: 00 width: 32 bits clock: 66MHz capabilities: ohci bus_master configuration: driver=ohci_hcd latency=64 resources: irq:16 memory:f7ffe000-f7ffefff *-usb:2 description: USB Controller product: SB700/SB800 USB EHCI Controller vendor: ATI Technologies Inc physical id: 12.2 bus info: pci@0000:00:12.2 version: 00 width: 32 bits clock: 66MHz capabilities: pm debug ehci bus_master cap_list configuration: driver=ehci_hcd latency=64 resources: irq:17 memory:f7fff800-f7fff8ff *-usb:3 description: USB Controller product: SB700/SB800 USB OHCI0 Controller vendor: ATI Technologies Inc physical id: 13 bus info: pci@0000:00:13.0 version: 00 width: 32 bits clock: 66MHz capabilities: ohci bus_master configuration: driver=ohci_hcd latency=64 resources: irq:18 memory:f7ffb000-f7ffbfff *-usb:4 description: USB Controller product: SB700 USB OHCI1 Controller vendor: ATI Technologies Inc physical id: 13.1 bus info: pci@0000:00:13.1 version: 00 width: 32 bits clock: 66MHz capabilities: ohci bus_master configuration: driver=ohci_hcd latency=64 resources: irq:18 memory:f7ffc000-f7ffcfff *-usb:5 description: USB Controller product: SB700/SB800 USB EHCI Controller vendor: ATI Technologies Inc physical id: 13.2 bus info: pci@0000:00:13.2 version: 00 width: 32 bits clock: 66MHz capabilities: pm debug ehci bus_master cap_list configuration: driver=ehci_hcd latency=64 resources: irq:19 memory:f7fff400-f7fff4ff *-serial UNCLAIMED description: SMBus product: SBx00 SMBus Controller vendor: ATI Technologies Inc physical id: 14 bus info: pci@0000:00:14.0 version: 3c width: 32 bits clock: 66MHz capabilities: ht cap_list configuration: latency=0 *-ide description: IDE interface product: SB700/SB800 IDE Controller vendor: ATI Technologies Inc physical id: 14.1 bus info: pci@0000:00:14.1 logical name: scsi5 version: 00 width: 32 bits clock: 66MHz capabilities: ide msi bus_master cap_list emulated configuration: driver=pata_atiixp latency=64 resources: irq:16 ioport:1f0(size=8) ioport:3f6 ioport:170(size=8) ioport:376 ioport:ff00(size=16) *-cdrom:0 description: DVD reader product: DVDROM DH16NS30 vendor: HL-DT-ST physical id: 0.0.0 bus info: scsi@5:0.0.0 logical name: /dev/cdrom1 logical name: /dev/dvd1 logical name: /dev/scd0 logical name: /dev/sr0 version: 1.00 capabilities: removable audio dvd configuration: ansiversion=5 status=nodisc *-cdrom:1 description: DVD-RAM writer product: DVDRAM GH22NS50 vendor: HL-DT-ST physical id: 0.1.0 bus info: scsi@5:0.1.0 logical name: /dev/cdrom logical name: /dev/cdrw logical name: /dev/dvd logical name: /dev/dvdrw logical name: /dev/scd1 logical name: /dev/sr1 version: TN02 capabilities: removable audio cd-r cd-rw dvd dvd-r dvd-ram configuration: ansiversion=5 status=nodisc *-multimedia description: Audio device product: SBx00 Azalia (Intel HDA) vendor: ATI Technologies Inc physical id: 14.2 bus info: pci@0000:00:14.2 version: 00 width: 64 bits clock: 33MHz capabilities: pm bus_master cap_list configuration: driver=HDA Intel latency=64 resources: irq:16 memory:f7ff4000-f7ff7fff *-isa description: ISA bridge product: SB700/SB800 LPC host controller vendor: ATI Technologies Inc physical id: 14.3 bus info: pci@0000:00:14.3 version: 00 width: 32 bits clock: 66MHz capabilities: isa bus_master configuration: latency=0 *-pci:4 description: PCI bridge product: SBx00 PCI to PCI Bridge vendor: ATI Technologies Inc physical id: 14.4 bus info: pci@0000:00:14.4 version: 00 width: 32 bits clock: 66MHz capabilities: pci subtractive_decode bus_master resources: ioport:e000(size=4096) memory:fbf00000-fbffffff *-network description: Ethernet interface product: 82541PI Gigabit Ethernet Controller vendor: Intel Corporation physical id: 5 bus info: pci@0000:05:05.0 logical name: eth1 version: 05 serial: 00:1b:21:56:f3:60 size: 100MB/s capacity: 1GB/s width: 32 bits clock: 66MHz capabilities: pm pcix bus_master cap_list rom ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt-fd autonegotiation configuration: autonegotiation=on broadcast=yes driver=e1000 driverversion=7.3.21-k6-NAPI duplex=full firmware=N/A ip=192.168.1.2 latency=64 link=yes mingnt=255 multicast=yes port=twisted pair speed=100MB/s resources: irq:20 memory:fbfe0000-fbffffff memory:fbfc0000-fbfdffff ioport:ec00(size=64) memory:fbfa0000-fbfbffff *-usb:6 description: USB Controller product: SB700/SB800 USB OHCI2 Controller vendor: ATI Technologies Inc physical id: 14.5 bus info: pci@0000:00:14.5 version: 00 width: 32 bits clock: 66MHz capabilities: ohci bus_master configuration: driver=ohci_hcd latency=64 resources: irq:18 memory:f7ffa000-f7ffafff *-pci:1 description: Host bridge product: Family 10h Processor HyperTransport Configuration vendor: Advanced Micro Devices [AMD] physical id: 101 bus info: pci@0000:00:18.0 version: 00 width: 32 bits clock: 33MHz *-pci:2 description: Host bridge product: Family 10h Processor Address Map vendor: Advanced Micro Devices [AMD] physical id: 102 bus info: pci@0000:00:18.1 version: 00 width: 32 bits clock: 33MHz *-pci:3 description: Host bridge product: Family 10h Processor DRAM Controller vendor: Advanced Micro Devices [AMD] physical id: 103 bus info: pci@0000:00:18.2 version: 00 width: 32 bits clock: 33MHz *-pci:4 description: Host bridge product: Family 10h Processor Miscellaneous Control vendor: Advanced Micro Devices [AMD] physical id: 104 bus info: pci@0000:00:18.3 version: 00 width: 32 bits clock: 33MHz configuration: driver=k10temp resources: irq:0 *-pci:5 description: Host bridge product: Family 10h Processor Link Control vendor: Advanced Micro Devices [AMD] physical id: 105 bus info: pci@0000:00:18.4 version: 00 width: 32 bits clock: 33MHz *-scsi physical id: 1 bus info: usb@2:3 logical name: scsi8 capabilities: emulated scsi-host configuration: driver=usb-storage *-disk:0 description: SCSI Disk physical id: 0.0.0 bus info: scsi@8:0.0.0 logical name: /dev/sdc *-disk:1 description: SCSI Disk physical id: 0.0.1 bus info: scsi@8:0.0.1 logical name: /dev/sdd *-disk:2 description: SCSI Disk physical id: 0.0.2 bus info: scsi@8:0.0.2 logical name: /dev/sde *-disk:3 description: SCSI Disk physical id: 0.0.3 bus info: scsi@8:0.0.3 logical name: /dev/sdf *-network DISABLED description: Ethernet interface physical id: 1 logical name: vboxnet0 serial: 0a:00:27:00:00:00 capabilities: ethernet physical configuration: broadcast=yes multicast=yes

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• Boot From a USB Drive Even if your BIOS Won’t Let You

  - by Trevor Bekolay

  You’ve always got a trusty bootable USB flash drive with you to solve computer problems, but what if a PC’s BIOS won’t let you boot from USB? We’ll show you how to make a CD or floppy disk that will let you boot from your USB drive. This boot menu, like many created before USB drives became cheap and commonplace, does not include an option to boot from a USB drive. A piece of freeware called PLoP Boot Manager solves this problem, offering an image that can burned to a CD or put on a floppy disk, and enables you to boot to a variety of devices, including USB drives. Put PLoP on a CD PLoP comes as a zip file, which includes a variety of files. To put PLoP on a CD, you will need either plpbt.iso or plpbtnoemul.iso from that zip file. Either disc image should work on most computers, though if in doubt plpbtnoemul.iso should work “everywhere,” according to the readme included with PLoP Boot Manager. Burn plpbtnoemul.iso or plpbt.iso to a CD and then skip to the “booting PLoP Boot Manager” section. Put PLoP on a Floppy Disk If your computer is old enough to still have a floppy drive, then you will need to put the contents of the plpbt.img image file found in PLoP’s zip file on a floppy disk. To do this, we’ll use a freeware utility called RawWrite for Windows. We aren’t fortunate enough to have a floppy drive installed, but if you do it should be listed in the Floppy drive drop-down box. Select your floppy drive, then click on the “…” button and browse to plpbt.img. Press the Write button to write PLoP boot manager to your floppy disk. Booting PLoP Boot Manager To boot PLoP, you will need to have your CD or floppy drive boot with higher precedence than your hard drive. In many cases, especially with floppy disks, this is done by default. If the CD or floppy drive is not set to boot first, then you will need to access your BIOS’s boot menu, or the setup menu. The exact steps to do this vary depending on your BIOS – to get a detailed description of the process, search for your motherboard’s manual (or your laptop’s manual if you’re working with a laptop). In general, however, as the computer boots up, some important keyboard strokes are noted somewhere prominent on the screen. In our case, they are at the bottom of the screen. Press Escape to bring up the Boot Menu. Previously, we burned a CD with PLoP Boot Manager on it, so we will select the CD-ROM Drive option and hit Enter. If your BIOS does not have a Boot Menu, then you will need to access the Setup menu and change the boot order to give the floppy disk or CD-ROM Drive higher precedence than the hard drive. Usually this setting is found in the “Boot” or “Advanced” section of the Setup menu. If done correctly, PLoP Boot Manager will load up, giving a number of boot options. Highlight USB and press Enter. PLoP begins loading from the USB drive. Despite our BIOS not having the option, we’re now booting using the USB drive, which in our case holds an Ubuntu Live CD! This is a pretty geeky way to get your PC to boot from a USB…provided your computer still has a floppy drive. Of course if your BIOS won’t boot from a USB it probably has one…or you really need to update it. Download PLoP Boot Manager Download RawWrite for Windows Similar Articles Productive Geek Tips Create a Bootable Ubuntu 9.10 USB Flash DriveReinstall Ubuntu Grub Bootloader After Windows Wipes it OutCreate a Bootable Ubuntu USB Flash Drive the Easy WayBuilding a New Computer – Part 3: Setting it UpInstall Windows XP on Your Pre-Installed Windows Vista Computer TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 Office 2010 reviewed in depth by Ed Bott FoxClocks adds World Times in your Statusbar (Firefox) Have Fun Editing Photo Editing with Citrify Outlook Connector Upgrade Error Gadfly is a cool Twitter/Silverlight app Enable DreamScene in Windows 7

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• cannot make ubuntu 64-bit v12.04 install work

  - by honestann

  I decided it was time to update my ubuntu (single boot) computer from 64-bit v10.04 to 64-bit v12.04. Unfortunately, for some reason (or reasons) I just can't make it work. Note that I am attempting a fresh install of 64-bit v12.04 onto a new 3TB hard disk, not an upgrade of the 1TB hard disk that contains my working 64-bit v10.04 installation. To perform the attempted install of v12.04 I unplug the SATA cable from the 1TB drive and plug it into the 3TB drive (to avoid risking damage to my working v10.04 installation). I downloaded the ubuntu 64-bit v12.04 install DVD ISO file (~1.6 GB) from the ubuntu releases webpage and burned it onto a DVD. I have downloaded the DVD ISO file 3 times and burned 3 of these installation DVDs (twice with v10.04 and once with my winxp64 system), but none of them work. I run the "check disk" on the DVDs at the beginning of the installation process to assure the DVD is valid. When installation completes and the system boots the 3TB drive, it reports "unknown filesystem". After installation on the 250GB drives, the system boots up fine. During every install I plug the same SATA cable (sda) into only one disk drive (the 3TB or one of the 250GB drives) and leave the other disk drives unconnected (for simplicity). It is my understanding that 64-bit ubuntu (and 64-bit linux in general) has no problem with 3TB disk drives. In the BIOS I have tried having EFI set to "enabled" and "auto" with no apparent difference (no success). I never bothered setting the BIOS to "non-EFI". I have tried partitioning the drive in a few ways to see if that makes a difference, but so far it has not mattered. Typically I manually create partitions something like this: 8GB /boot ext4 8GB swap 3TB / ext4 But I've also tried the following, just in case it matters: 8GB boot efi 8GB swap 8GB /boot ext4 3TB / ext4 Note: In the partition dialog I specify bootup on the same drive I am partitioning and installing ubuntu v12.04 onto. It is a VERY DANGEROUS FACT that the default for this always comes up with the wrong drive (some other drive, generally the external drive). Unless I'm stupid or misunderstanding something, this is very wrong and very dangerous default behavior. Note: If I connect the SATA cable to the 1TB drive that has been my ubuntu 64-bit v10.04 system drive for the past 2 years, it boots up and runs fine. I guess there must be a log file somewhere, and maybe it gives some hints as to what the problem is. I should be able to boot off the 1TB drive with the 3TB drive connected as a secondary (non-boot) drive and get the log file, assuming there is one and someone tells me the name (and where to find it if the name is very generic). After installation on the 3TB drive completes and the system reboots, the following prints out on a black screen: Loading Operating System ... Boot from CD/DVD : Boot from CD/DVD : error: unknown filesystem grub rescue> Note: I have two DVD burners in the system, hence the duplicate line above. Note: I install and boot 64-bit ubuntu v12.04 on both of my 250GB in this same system, but still cannot make the 3TB drive boot. Sigh. Any ideas? ========== motherboard == gigabyte 990FXA-UD7 CPU == AMD FX-8150 8-core bulldozer @ 3.6 GHz RAM == 8GB of DDR3 in 2 sticks (matched pair) HDD == seagate 3TB SATA3 @ 7200 rpm (new install 64-bit v12.04 FAILS) HDD == seagate 1TB SATA3 @ 7200 rpm (64-bit v10.04 WORKS for two years) HDD == seagate 250GB SATA2 @ 7200 rpm (new install 64-bit v12.04 WORKS) HDD == seagate 250GB SATA2 @ 7200 rpm (new install 64-bit v12.04 WORKS) GPU == nvidia GTX-285 ??? == no overclocking or other funky business USB == external seagate 2TB HDD for making backups DVD == one bluray burner (SATA) DVD == one DVD burner (SATA) 64-bit ubuntu v10.04 has booted and run fine on the seagate 1TB drive for 2 years.

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• Install Problem (Ubuntu Server 10.04) with USB as it reboots when I hit 'enter' for 'Install Ubuntu Server' option! Help

  - by Alastair

  We cannot seem to install Ubuntu Server with USB as it reboots when I hit 'enter' for 'Install Ubuntu Server' option. My friend wants to try setting up a server so; we downloaded Ubuntu Server 10.04.4 we created a boot CD and installed ubuntu server no problem at all. But then the problem arose the hardrive we wanted to use is a 1tb sata drive and the computer orginally has 40gb IDE. So I bought a Sata to IDE and IDE to Sata converter from: http://www.microdirect.co.uk/Home/Product/52926/IDE-to-SATA-converter---Converts-IDE-HDD-to-SATA-inc-sata-data-and-power-cables Unfortunately this converter means I cannot plug in the IDE cable meaning I only have one IDE connection i.e CD drive has to be disconnected for the 1tb sata Hardrive to be connected. So now the 1tb drive is connected, powered it on opened the bios to make sure the hdd appeared it did as ST3ASDAPFKG (somthing like that). Fortunately the computer supports USB booting, so I read ubuntu server usb install instructions I tried: Startup Disk Creator & Unebootin Startup Disk Creator made the usb bootable with the 'ubuntu-10.04.4-server-i386.iso' All looked fine stuck the usb drive in, booted the machine up and I am quickly presented with ubuntu language choice. I hit enter to select English then I am presented with: Install Ubuntu Server, Install Ubuntu Enterprise Cloud, Check Disk for defects, test memory, Boot from first hard disk, Rescue a broken system I can move up and down the menu fine everything seems ok, I select 'Install Ubuntu Server', computer just hangs and screen either goes blank or locks. So I rebooted the computer loads the same menus fine, I select 'Install Ubuntu Server' hit 'enter' and the computer just restarts then brings me back to the same menu. hmmm Then I tried choosing the rest of the options separately: Install Ubuntu Server, Install Ubuntu Enterprise Cloud, Check Disk for defects, test memory, Boot from first hard disk, Rescue a broken system computer just restarts and back to the same ubuntu menu every-time. Grrrr At this point I wish I actually new how to command line install or something but I don't have a clue how to do that. So I tried hitting 'f6' for 'other options' and I tried them all in various combinations and individually. No Luck: (Expert mode, acpi=off, noapic, nolapic, edd=on, nodmraid, nomodeset, Free Software only) At this point I am wondering if it is a bios setting causing problems, I tried turning every option in there on off that I don't understand. No Luck. I then discovered by accident if you hit esc in the ubuntu install menu it says "you are leaving the graphical boot menu and starting the text mode interface" I hit 'Ok'. Next a prompt pops up saying 'boot:' One time it responded when I typed somthing with 'Cannot find kernal image (something like that but since then it just restarts when I hit enter in that prompt). I had a browse on the net and found someone suggesting removing quiet from install command for 'Install Ubuntu Server'. Made no difference at all just reboots... Orginal boot options noprompt cdrom-detect/try-usb=true persistent file=/cdrom/preseed/ubuntu-server.seed initrd=/install/initrd.gz quiet -- Modified boot options noprompt cdrom-detect/try-usb=true persistent file=/cdrom/preseed/ubuntu-server.seed initrd=/install/initrd.gz -- Still I cannot install Ubuntu Server by USB as it, reboots when I hit 'enter' for 'Install Ubuntu Server' option. This is a real pain as we cannot take the 1tb Sata Hardrive and swap it for IDE to be able to use the cd drive. Why is is it so hard to install ubuntu server with usb? I have wasted a full day and half on this really frustrated any help would be amazing! I know the answers out there just seems a bit illusive at the moment! Computer Spec- Asus Motherboard, 1gb RAM 2X512MB, Powersupply 200watt, 2.8ghz Processor Intel, On-board 64mb graphics, 100mb Ethernet, 54mb Wireless,

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• help: cannot make ubuntu 64-bit v12.04 install work

  - by honestann

  I decided it was time to update my ubuntu (single boot) computer from 64-bit v10.04 to 64-bit v12.04. Unfortunately, for some reason (or reasons) I just can't make it work. Note that I am attempting a fresh install of 64-bit v12.04 onto a new 3TB hard disk, not an upgrade of the 1TB hard disk that has contained my 64-bit v10.04 installation. To perform the attempted install of v12.04 I unplug the SATA cable from the 1TB drive and plug it into the 3TB drive (to avoid risking damage to my working v10.04 installation). I downloaded the ubuntu 64-bit v12.04 install DVD ISO file (~1.6 GB) from the ubuntu releases webpage and burned it onto a DVD. I have downloaded the DVD ISO file 3 times and burned 3 of these installation DVDs (twice with v10.04 and once with my winxp64 system), but none of them work. I run the "check disk" on the DVDs at the beginning of the installation process to assure the DVD is valid. I also tried to install on two older 250GB seagate drives in the same computer. During every attempt I plug the same SATA cable (sda) into only one disk drive (the 3TB or one of the 250GB drives) and leave the other disk drives unconnected (for simplicity). Installation takes about 30 minutes on the 250GB drives, and about 60 minutes on the 3TB drive - not sure why. When I install on the 250GB drives, the install process finishes, the computer reboots (after the install DVD is removed), but I get a grub error 15. It is my understanding that 64-bit ubuntu (and 64-bit linux in general) has no problem with 3TB disk drives. In the BIOS I have tried having EFI set to "enabled" and "auto" with no apparent difference (no success). I have tried partitioning the drive in a few ways to see if that makes a difference, but so far it has not mattered. Typically I manually create partitions something like this: 8GB swap 8GB /boot ext4 3TB / ext4 But I've also tried the following, just in case it matters: 100MB boot efi 8GB swap 8GB /boot ext4 3TB / ext4 Note: In the partition dialog I specify bootup on the same drive I am partitioning and installing ubuntu v12.04 onto. It is a VERY DANGEROUS FACT that the default for this always comes up with the wrong drive (some other drive, generally the external drive). Unless I'm stupid or misunderstanding something, this is very wrong and very dangerous default behavior. Note: If I connect the SATA cable to the 1TB drive that has been my ubuntu 64-bit v10.04 system drive for the past 2 years, it boots up and runs fine. I guess there must be a log file somewhere, and maybe it gives some hints as to what the problem is. I should be able to boot off the 1TB drive with the 3TB drive connected as a secondary (non-boot) drive and get the log file, assuming there is one and someone tells me the name (and where to find it if the name is very generic). After installation on the 3TB drive completes and the system reboots, the following prints out on a black screen: Loading Operating System ... Boot from CD/DVD : Boot from CD/DVD : error: unknown filesystem grub rescue Note: I have two DVD burners in the system, hence the duplicate line above. The same install and reboot on the 250GB drives generates "grub error 15". Sigh. Any ideas? ========== motherboard == gigabyte 990FXA-UD7 CPU == AMD FX-8150 8-core bulldozer @ 3.6 GHz RAM == 8GB of DDR3 in 2 sticks (matched pair) HDD == seagate 3TB SATA3 @ 7200 rpm (new install 64-bit v12.04) HDD == seagate 1TB SATA3 @ 7200 rpm (current install 64-bit v10.04) GPU == nvidia GTX-285 ??? == no overclocking or other funky business USB == external seagate 2TB HDD for making backups DVD == one bluray burner (SATA) DVD == one DVD burner (SATA) The current ubuntu 64-bit v10.04 system boots and runs fine on a seagate 1TB.

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• problem with network-manager-pptp

  - by Riuzaki90

  I've a problema with the VPA CAble connection of my university... on the website of the university there's a .sh file that set all the variables of the connection in ETC/PPP/PEERS and another .sh file that call the connection...I'm on ubuntu 11.10 and when I run the setup.sh I have this error: impossible to find network-manager-pptp these are the two file that I had talk about: #!/bin/bash echo "Creazione della connessione in corso attendere........." apt-get update apt-get install pptp-linux network-manager-pptp echo -n "Digitare la propria Username: " read USERNAME echo -n "Digitare la propria Password: " read PASSWORD pptpsetup --create UNICAL_Campus_Access --server 160.97.73.253 --username $USERNAME --password $PASSWORD echo 'pty "pptp 160.97.73.253 --nolaunchpppd"' >/etc/ppp/peers/UNICAL_Campus_Access echo 'require-mppe-128' >>/etc/ppp/peers/UNICAL_Campus_Access echo 'file /etc/ppp/options.pptp'>>/etc/ppp/peers/UNICAL_Campus_Access echo 'name '$USERNAME''>>/etc/ppp/peers/UNICAL_Campus_Access echo 'remotename PPTP'>>/etc/ppp/peers/UNICAL_Campus_Access echo 'ipparam UNICAL_Campus_Access'>>/etc/ppp/peers/UNICAL_Campus_Access echo $USERNAME' PPTP '$PASSWORD' *'>>/etc/ppp/chap-secrets rm /etc/ppp/options.pptp echo '###############################################################################'>/etc/ppp/options.pptp echo '# $Id: options.pptp,v 1.3 2006/03/26 23:11:05 quozl Exp $'>>/etc/ppp/options.pptp echo '#'>>/etc/ppp/options.pptp echo '# Sample PPTP PPP options file /etc/ppp/options.pptp'>>/etc/ppp/options.pptp echo '# Options used by PPP when a connection is made by a PPTP client.'>>/etc/ppp/options.pptp echo '# This file can be referred to by an /etc/ppp/peers file for the tunnel.'>>/etc/ppp/options.pptp echo '# Changes are effective on the next connection. See "man pppd".'>>/etc/ppp/options.pptp echo '#'>>/etc/ppp/options.pptp echo '# You are expected to change this file to suit your system. As'>>/etc/ppp/options.pptp echo '# packaged, it requires PPP 2.4.2 or later from http://ppp.samba.org/'>>/etc/ppp/options.pptp echo '# and the kernel MPPE module available from the CVS repository also on'>>/etc/ppp/options.pptp echo '# http://ppp.samba.org/, which is packaged for DKMS as kernel_ppp_mppe.'>>/etc/ppp/options.pptp echo '###############################################################################'>>/etc/ppp/options.pptp echo '# Lock the port'>>/etc/ppp/options.pptp echo 'lock'>>/etc/ppp/options.pptp echo '# Authentication'>>/etc/ppp/options.pptp echo '# We do not need the tunnel server to authenticate itself'>>/etc/ppp/options.pptp echo 'noauth'>>/etc/ppp/options.pptp echo '#We won"t do PAP, EAP, CHAP, or MSCHAP, but we will accept MSCHAP-V2'>>/etc/ppp/options.pptp echo '#(you may need to remove these refusals if the server is not using MPPE)'>>/etc/ppp/options.pptp echo 'refuse-pap'>>/etc/ppp/options.pptp echo 'refuse-eap'>>/etc/ppp/options.pptp echo 'refuse-chap'>>/etc/ppp/options.pptp echo 'refuse-mschap'>>/etc/ppp/options.pptp echo '# Compression Turn off compression protocols we know won"t be used'>>/etc/ppp/options.pptp echo 'nobsdcomp'>>/etc/ppp/options.pptp echo 'nodeflate'>>/etc/ppp/options.pptp echo '# Encryption'>>/etc/ppp/options.pptp echo '# (There have been multiple versions of PPP with encryption support,'>>/etc/ppp/options.pptp echo '# choose with of the following sections you will use. Note that MPPE'>>/etc/ppp/options.pptp echo '# requires the use of MSCHAP-V2 during authentication)'>>/etc/ppp/options.pptp echo '# http://ppp.samba.org/ the PPP project version of PPP by Paul Mackarras'>>/etc/ppp/options.pptp echo '# ppp-2.4.2 or later with MPPE only, kernel module ppp_mppe.o'>>/etc/ppp/options.pptp echo '#{{{'>>/etc/ppp/options.pptp echo '# Require MPPE 128-bit encryption'>>/etc/ppp/options.pptp echo '#require-mppe-128'>>/etc/ppp/options.pptp echo '#}}}'>>/etc/ppp/options.pptp echo '# http://polbox.com/h/hs001/ fork from PPP project by Jan Dubiec'>>/etc/ppp/options.pptp echo '#ppp-2.4.2 or later with MPPE and MPPC, kernel module ppp_mppe_mppc.o'>>/etc/ppp/options.pptp echo '#{{{'>>/etc/ppp/options.pptp echo '# Require MPPE 128-bit encryption'>>/etc/ppp/options.pptp echo '#mppe required,stateless'>>/etc/ppp/options.pptp echo '# }}}'>>/etc/ppp/options.pptp echo "setup di 'UNICAL Campus Access' terminato correttamente" echo "per connettersi eseguire lo script 'UNICAL_Campus_Access.sh' " and the second: #!/bin/bash echo "Connessione alla Rete del Centro Residenziale in corso attendere........." modprobe ppp_mppe pppd call UNICAL_Campus_Access sleep 30 tail -n 8 /var/log/messages echo "Connessione Stabilita" echo -n "Per terminare la connessione premere invio (in alternativa eseguire il commando 'killall pppd'):----> " read CONN killall pppd echo "Connessione terminata" I've correctly installed network-manager-pptp to the latest version...help?

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• Grub Rescue Unknown Filesystem Error. Grub Corrupted or Filesystem?

  - by nightcrawler

  Now it has happened twice & have been pulling my hairs now... I have installed xubuntu on my external hardisk & have been using it for about 3 months. It has three partitions, one of 500 mb mounted at /boot, 2nd one of 48gb mounted at / & the rest (out of 160gb) is ntfs partition....used as normal external storage. The last storage supposedly acts as a buffer b/w Linux distributions & Win platform, buffer in the sense that it provides a universal channel for data transfers. I have constantly used this external hardisk for data transfers b/w win7 laptop & xubuntu (on this external hd) without any hassle. However, on of my desktops where I have ubuntu I (for the first time) attached this external drive which let me do data transfers where all three partitions properly mounted....but then nasty thing occurred the same that occurred before. I (as usual) tried booting via this external hd (one having xubuntu, one having being formerly used under Ubuntu) I got error Now I am totally devastated because similar thing happened ~6months before when I had fedora 17 in my external hd (instead of xubuntu) & after it was used under ubuntu the same happened...i didn't reported it because I already had planned towards debian instead of rpm! The mystery is that as long as I don't attach this external hd under ubuntu the data never** corrupts whereas under win xp/7 I can use it as a normal usb storage of coarse linux partitions aren’t available under win platforms... **From corrupts I mean hd fails to boot with the error mentioned however cant say whether data within remains untouched? It seems that my grub & or MBR is corrupted. Please sir guide me to solve this issue also why I cant attach & use linux external hds under linux platform Disk /dev/sdc: 160.0 GB, 160041884672 bytes 255 heads, 63 sectors/track, 19457 cylinders, total 312581806 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x0004e7d0 Device Boot Start End Blocks Id System /dev/sdc1 * 2048 976895 487424 83 Linux /dev/sdc2 978942 96874495 47947777 5 Extended /dev/sdc3 96874496 312575999 107850752 7 HPFS/NTFS/exFAT /dev/sdc5 978944 94726143 46873600 83 Linux /dev/sdc6 94728192 96874495 1073152 82 Linux swap / Solaris I can recall for sure that have seen a thread here when a similar problem occurred & in response someone gave solution of how to mount (now invisible) partitions & recover important data in them. I have misplaced that URL so if any can guide me thither because my important documents resides in / partition What I already have done: Without success I have tried this & related solutions What I plan to do: I believe that filesystem has corrupted & would you recommend solution like this provided I cant recall whether my /boot (500mb) partition was ext4 or ext2 though I am sure that my / (48gb) partition was ext4 UPDATE 1 Attached my external hd under Ubuntu ran followinf command as root grub-install /dev/sdc where /dev/sdc was my external hd containing corrupted xubuntu....it reported all done! I re-ran fdisk -l but to my disappointment it reported Disk /dev/sdc: 160.0 GB, 160041884672 bytes 255 heads, 63 sectors/track, 19457 cylinders, total 312581806 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x1b6b9167 Disk /dev/sdc doesn't contain a valid partition table ...& now I can't even access its ntfs partition (former /dev/sdc3) please help? UPDATE 2 TestDisk (by cgsecurity) failed at founding any partition table :( TestDisk 6.13, Data Recovery Utility, November 2011 Christophe GRENIER <[email protected]> http://www.cgsecurity.org Disk /dev/sdc - 160 GB / 149 GiB - CHS 19457 255 63 Partition Start End Size in sectors

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• Oh no! My padding's invalid!

  - by Simon Cooper

  Recently, I've been doing some work involving cryptography, and encountered the standard .NET CryptographicException: 'Padding is invalid and cannot be removed.' Searching on StackOverflow produces 57 questions concerning this exception; it's a very common problem encountered. So I decided to have a closer look. To test this, I created a simple project that decrypts and encrypts a byte array: // create some random data byte[] data = new byte[100]; new Random().NextBytes(data); // use the Rijndael symmetric algorithm RijndaelManaged rij = new RijndaelManaged(); byte[] encrypted; // encrypt the data using a CryptoStream using (var encryptor = rij.CreateEncryptor()) using (MemoryStream encryptedStream = new MemoryStream()) using (CryptoStream crypto = new CryptoStream( encryptedStream, encryptor, CryptoStreamMode.Write)) { crypto.Write(data, 0, data.Length); encrypted = encryptedStream.ToArray(); } byte[] decrypted; // and decrypt it again using (var decryptor = rij.CreateDecryptor()) using (CryptoStream crypto = new CryptoStream( new MemoryStream(encrypted), decryptor, CryptoStreamMode.Read)) { byte[] decrypted = new byte[data.Length]; crypto.Read(decrypted, 0, decrypted.Length); } Sure enough, I got exactly the same CryptographicException when trying to decrypt the data even in this simple example. Well, I'm obviously missing something, if I can't even get this single method right! What does the exception message actually mean? What am I missing? Well, after playing around a bit, I discovered the problem was fixed by changing the encryption step to this: // encrypt the data using a CryptoStream using (var encryptor = rij.CreateEncryptor()) using (MemoryStream encryptedStream = new MemoryStream()) { using (CryptoStream crypto = new CryptoStream( encryptedStream, encryptor, CryptoStreamMode.Write)) { crypto.Write(data, 0, data.Length); } encrypted = encryptedStream.ToArray(); } Aaaah, so that's what the problem was. The CryptoStream wasn't flushing all it's data to the MemoryStream before it was being read, and closing the stream causes it to flush everything to the backing stream. But why does this cause an error in padding? Cryptographic padding All symmetric encryption algorithms (of which Rijndael is one) operates on fixed block sizes. For Rijndael, the default block size is 16 bytes. This means the input needs to be a multiple of 16 bytes long. If it isn't, then the input is padded to 16 bytes using one of the padding modes. This is only done to the final block of data to be encrypted. CryptoStream has a special method to flush this final block of data - FlushFinalBlock. Calling Stream.Flush() does not flush the final block, as you might expect. Only by closing the stream or explicitly calling FlushFinalBlock is the final block, with any padding, encrypted and written to the backing stream. Without this call, the encrypted data is 16 bytes shorter than it should be. If this final block wasn't written, then the decryption gets to the final 16 bytes of the encrypted data and tries to decrypt it as the final block with padding. The end bytes don't match the padding scheme it's been told to use, therefore it throws an exception stating what is wrong - what the decryptor expects to be padding actually isn't, and so can't be removed from the stream. So, as well as closing the stream before reading the result, an alternative fix to my encryption code is the following: // encrypt the data using a CryptoStream using (var encryptor = rij.CreateEncryptor()) using (MemoryStream encryptedStream = new MemoryStream()) using (CryptoStream crypto = new CryptoStream( encryptedStream, encryptor, CryptoStreamMode.Write)) { crypto.Write(data, 0, data.Length); // explicitly flush the final block of data crypto.FlushFinalBlock(); encrypted = encryptedStream.ToArray(); } Conclusion So, if your padding is invalid, make sure that you close or call FlushFinalBlock on any CryptoStream performing encryption before you access the encrypted data. Flush isn't enough. Only then will the final block be present in the encrypted data, allowing it to be decrypted successfully.

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• Grub2 : Windows 7 can't boot installing with Ubuntu 10.04 on different hard drive

  - by dellphi

  I use a dual boot with two hard disks and two OS is Ubuntu 10.04 and Windows 7. Windows 7 installed on the first disk, first partition. Grub is installed on a second hard disk MBR, and Ubuntu installed on an extended partition on a second hard drive. When I select Windows 7 on the Grub menu, the HDD lamp lights up briefly and then black screen on the monitor, with the status of the keyboard is still functioning. Until now (with the default boot from first HDD), I have to press F12 to get into the Grub to run Linux on a second HDD. ================ fdisk -l ================================ dellph1@dellph1-desktop:~$ fdisk -l omitting empty partition (5) Disk /dev/sda: 1000.2 GB, 1000204886016 bytes 255 heads, 63 sectors/track, 121601 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00087dec Device Boot Start End Blocks Id System /dev/sda1 * 1 23104 185582848+ 7 HPFS/NTFS /dev/sda2 23105 121601 791177122 5 Extended /dev/sda5 36107 74408 307660783+ 7 HPFS/NTFS /dev/sda6 74409 100081 206218341 7 HPFS/NTFS /dev/sda7 100082 121601 172859368+ 7 HPFS/NTFS Disk /dev/sdb: 160.0 GB, 160041885696 bytes 255 heads, 63 sectors/track, 19457 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x6d43dfb2 Device Boot Start End Blocks Id System /dev/sdb1 1 10030 80560066 5 Extended /dev/sdb5 * 1 5560 44657601 83 Linux /dev/sdb6 5560 9387 30736384 83 Linux /dev/sdb7 9387 10030 5164032 82 Linux swap / Solaris dellph1@dellph1-desktop:~$ ================= grub.cfg ================== # DO NOT EDIT THIS FILE # It is automatically generated by /usr/sbin/grub-mkconfig using templates from /etc/grub.d and settings from /etc/default/grub # BEGIN /etc/grub.d/00_header if [ -s $prefix/grubenv ]; then load_env fi set default="0" if [ ${prev_saved_entry} ]; then set saved_entry=${prev_saved_entry} save_env saved_entry set prev_saved_entry= save_env prev_saved_entry set boot_once=true fi function savedefault { if [ -z ${boot_once} ]; then saved_entry=${chosen} save_env saved_entry fi } function recordfail { set recordfail=1 if [ -n ${have_grubenv} ]; then if [ -z ${boot_once} ]; then save_env recordfail; fi; fi } insmod ext2 set root='(hd1,5)' search --no-floppy --fs-uuid --set 2f014a3a-35f3-4d05-87aa-34ca677160b7 if loadfont /usr/share/grub/unicode.pf2 ; then set gfxmode=1024x768 insmod gfxterm insmod vbe if terminal_output gfxterm ; then true ; else # For backward compatibility with versions of terminal.mod that don't # understand terminal_output terminal gfxterm fi fi insmod ext2 set root='(hd1,5)' search --no-floppy --fs-uuid --set 2f014a3a-35f3-4d05-87aa-34ca677160b7 set locale_dir=($root)/boot/grub/locale set lang=en insmod gettext if [ ${recordfail} = 1 ]; then set timeout=-1 else set timeout=5 fi END /etc/grub.d/00_header BEGIN /etc/grub.d/05_debian_theme insmod ext2 set root='(hd1,5)' search --no-floppy --fs-uuid --set 2f014a3a-35f3-4d05-87aa-34ca677160b7 insmod jpeg if background_image /usr/share/backgrounds/CurlsbyCandy.jpg ; then set color_normal=white/black set color_highlight=black/light-gray else set menu_color_normal=white/black set menu_color_highlight=black/light-gray fi END /etc/grub.d/05_debian_theme BEGIN /etc/grub.d/10_linux menuentry 'Ubuntu, with Linux 2.6.32-24-generic' --class ubuntu --class gnu-linux --class gnu --class os { recordfail insmod ext2 set root='(hd1,5)' search --no-floppy --fs-uuid --set 2f014a3a-35f3-4d05-87aa-34ca677160b7 linux /boot/vmlinuz-2.6.32-24-generic root=UUID=2f014a3a-35f3-4d05-87aa-34ca677160b7 ro splash vga=795 quiet splash nomodeset video=uvesafb:mode_option=1280x1024-24,mtrr=3,scroll=ywrap initrd /boot/initrd.img-2.6.32-24-generic } menuentry 'Ubuntu, with Linux 2.6.32-24-generic (recovery mode)' --class ubuntu --class gnu-linux --class gnu --class os { recordfail insmod ext2 set root='(hd1,5)' search --no-floppy --fs-uuid --set 2f014a3a-35f3-4d05-87aa-34ca677160b7 echo 'Loading Linux 2.6.32-24-generic ...' linux /boot/vmlinuz-2.6.32-24-generic root=UUID=2f014a3a-35f3-4d05-87aa-34ca677160b7 ro single splash vga=795 echo 'Loading initial ramdisk ...' initrd /boot/initrd.img-2.6.32-24-generic } END /etc/grub.d/10_linux BEGIN /etc/grub.d/30_os-prober menuentry "Windows 7 (loader) (on /dev/sda1)" { insmod ntfs set root='(hd0,1)' search --no-floppy --fs-uuid --set 5cac2139ac210f58 chainloader +1 } END /etc/grub.d/30_os-prober BEGIN /etc/grub.d/40_multisystem Ajout de MultiSystem MULTISYSTEM MENU menuentry "PLoP Boot Manager" { linux16 /boot/plpbt } menuentry "Smart Boot Manager" { search --set -f /boot/sbootmgr.dsk linux16 /boot/memdisk initrd16 /boot/sbootmgr.dsk } FIN MULTISYSTEM MENU END /etc/grub.d/40_multisystem ================================================ I want to keep the Grub on the second HDD. I have been using the Startup Manager, Boot Manager and Grub Customizer, and this problem still unsolved. The easiest thing that I can possibly do is to install Grub on first HDD, but I was curious and maybe someone can help.

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