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  • On Linux, can I get 3D acceleration with a Nvidia card w/o X?

    - by anon
    I like Linux. I like OpenGL. I don't like X. On Linux, is there anyway to get 3D acceleration from my Nvidia card without X? Ideally, I'd have the kernel boot, get to a console, then somehow get into a "graphics mode", where my entire monitor is just a single OpenGL screen ... and I draw stuff to it with OpenGL. Without X. Is this possible? Thanks!

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  • Weird nfs performance: 1 thread better than 8, 8 better than 2!

    - by Joe
    I'm trying to determine the cause of poor nfs performance between two Xen Virtual Machines (client & server) running on the same host. Specifically, the speed at which I can sequentially read a 1GB file on the client is much lower than what would be expected based on the measured network connection speed between the two VMs and the measured speed of reading the file directly on the server. The VMs are running Ubuntu 9.04 and the server is using the nfs-kernel-server package. According to various NFS tuning resources, changing the number of nfsd threads (in my case kernel threads) can affect performance. Usually this advice is framed in terms of increasing the number from the default of 8 on heavily-used servers. What I find in my current configuration: RPCNFSDCOUNT=8: (default): 13.5-30 seconds to cat a 1GB file on the client so 35-80MB/sec RPCNFSDCOUNT=16: 18s to cat the file 60MB/s RPCNFSDCOUNT=1: 8-9 seconds to cat the file (!!?!) 125MB/s RPCNFSDCOUNT=2: 87s to cat the file 12MB/s I should mention that the file I'm exporting is on a RevoDrive SSD mounted on the server using Xen's PCI-passthrough; on the server I can cat the file in under seconds ( 250MB/s). I am dropping caches on the client before each test. I don't really want to leave the server configured with just one thread as I'm guessing that won't work so well when there are multiple clients, but I might be misunderstanding how that works. I have repeated the tests a few times (changing the server config in between) and the results are fairly consistent. So my question is: why is the best performance with 1 thread? A few other things I have tried changing, to little or no effect: increasing the values of /proc/sys/net/ipv4/ipfrag_low_thresh and /proc/sys/net/ipv4/ipfrag_high_thresh to 512K, 1M from the default 192K,256K increasing the value of /proc/sys/net/core/rmem_default and /proc/sys/net/core/rmem_max to 1M from the default of 128K mounting with client options rsize=32768, wsize=32768 From the output of sar -d I understand that the actual read sizes going to the underlying device are rather small (<100 bytes) but this doesn't cause a problem when reading the file locally on the client. The RevoDrive actually exposes two "SATA" devices /dev/sda and /dev/sdb, then dmraid picks up a fakeRAID-0 striped across them which I have mounted to /mnt/ssd and then bind-mounted to /export/ssd. I've done local tests on my file using both locations and see the good performance mentioned above. If answers/comments ask for more details I will add them.

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  • Installing ArchLinux into Ubuntu 12.04 root

    - by Johnny
    Is it possible to install 2 linux distros into 1 root, so they share same uuid and guid, configs and packages + same user /home folder ? For example: I have Ubuntu and Windows 7 already in dual boot on my laptop. Could I install Arch's base, base-devel and kernel, so it won't conflict with Ubuntu on the same root folder? P.S I don't feel like repartitioning my drive again, 'cause there's very complicated hierarchy, which occupies the entire disk. =)

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  • File size limit exceeded in bash

    - by yboren
    I have tried this shell script on a SUSE 10 server, kernel 2.6.16.60, ext3 filesystem the script has problem like this: cat file | awk '{print $1" "$2" "$3}' | sort -n > result the file's size is about 3.2G, and I get such error message: File size limit exceeded in this shell, ulimit -f is unlimited after I change script into this cat file | awk '{print $1" "$2" "$3}' >tmp sort -n tmp > result the problem is gone. I don't know why, can anyone help me with an explanation?

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  • Installing Hyper-V Integration Components on Linux

    - by Lance Fisher
    Some big news this week was Microsoft released the Hyper-V integration components for Linux source code under the GPL v2. I just installed Ubuntu Server 9.04 in a Hyper-V VM with a Legacy Network Adapter. How do I install the integration components? Do I have to wait until they are included in the kernel?

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  • VLAN issues between linux kernels 2.6 / 3.3 in an ESX / Cisco environment

    - by David Griffith
    I shall attempt to explain an issue I have encountered - I have a VM running on esx 4.1 with an interface connected to VLAN800 via an access port on a cisco 3750. It runs linux - kernel 2.6.24, and has about 5 to 10 Mbit of chatter on 10.10.0.0/16 and various multicast addresses to look after. I needed to isolate certain devices from certain other devices on the network, with all of them having to talk to that one VM. No, the address space can't be separated, nor can the networks be easily vlan'd apart. The software on the VM listens to one interface only. Private vlans appear to be the way to go. So as a test, I built a bridge on the VM that globs together the vlans as needed. All good, everything works as expected. But occasionally (sigh) there's some latency that trips up a couple of profinet devices on the network because, you know, you're not really supposed to trunk real-time protocols around the place willy-nilly. I shift it to our test/backup server - works nicely, but I don't want it to be running on the test server as we muck around with that a lot. So I says to myself, "I'll put it on a new VM for testing and tweaking." I download a small linux distro with kernel 3.3, and install as a new VM with a the vlans as separate interfaces for testing. I power up the testing VM - ok. I bring up all the separate interfaces - ok. I can ping the production VM, see all sorts of traffic going past with tshark, etc. I build a bridge and put the primary vlan on it - the production VM running 2.6 immediately loses its multicast traffic - Unicast is fine. (?) I shut down the bridge - still no multicast traffic (!?) I power-cycle the production VM(!?!?) - multicast traffic returns. I trunk everything into the testing VM and create vlan interfaces under linux instead - same result, as soon as I start the bridge.... no multicast on the production VM. Ok, so I take a break and leave things alone. I decide to play with a couple of ubiquiti bullet radios - I'm testing various firmware as a side project. I flash a radio with Open-wrt-12.09. I enable a trunk on a port on a cisco on our network so I can muck around with multiple vlans and SSIDs I power up the radio and connect - ok. I create a vlan interface from the trunk.... the same vlan as the production VM wayyyyy over there, three cisco routers away. Ok. I bridge the vlan interface to the wifi interface and immediately get a phone call. The production VM has (suprise!) lost its multicast traffic. Again, nothing comes back until I power-cycle the VM. What the hell is going on?

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  • Monitor number of bytes transferred to/from IP address on port.

    - by Mike
    Can anyone recommend a linux command line tool to monitor the number of bytes transferred between the local server and a specified IP address/port. The equivalent tcpdump command would be: tcpdump -s 0 -i any -w mycapture.trc port 80 host google.com which outputs : 46 packets captured 131 packets received by filter 0 packets dropped by kernel I'd like something similar that outputs: 54 bytes out, 176 bytes in I'd like it to work on RHEL and be free/open-source. It would be good if there was an existing tool which I was just missing too!

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  • Linux software RAID6: 3 drives offline - how to force online?

    - by Ole Tange
    This is similar to 3 drives fell out of Raid6 mdadm - rebuilding? except that it is not due to a failing cable. Instead the 3rd drive fell offline during rebuild of another drive. The drive failed with: kernel: end_request: I/O error, dev sdc, sector 293732432 kernel: md/raid:md0: read error not correctable (sector 293734224 on sdc). After rebooting both these sectors and the sectors around them are fine. This leads me to believe the error is intermittent and thus the device simply took too long to error correct the sector and remap it. I expect that no data was written to the RAID after it failed. Therefore I hope that if I can kick the last failing device online that the RAID is fine and that the xfs_filesystem is OK, maybe with a few missing recent files. Taking a backup of the disks in the RAID takes 24 hours, so I would prefer that the solution works the first time. I have therefore set up a test scenario: export PRE=3 parallel dd if=/dev/zero of=/tmp/raid${PRE}{} bs=1k count=1000k ::: 1 2 3 4 5 parallel mknod /dev/loop${PRE}{} b 7 ${PRE}{} \; losetup /dev/loop${PRE}{} /tmp/raid${PRE}{} ::: 1 2 3 4 5 mdadm --create /dev/md$PRE -c 4096 --level=6 --raid-devices=5 /dev/loop${PRE}[12345] cat /proc/mdstat mkfs.xfs -f /dev/md$PRE mkdir -p /mnt/disk2 umount -l /mnt/disk2 mount /dev/md$PRE /mnt/disk2 seq 1000 | parallel -j1 mkdir -p /mnt/disk2/{}\;cp /bin/* /mnt/disk2/{}\;sleep 0.5 & mdadm --fail /dev/md$PRE /dev/loop${PRE}3 /dev/loop${PRE}4 cat /proc/mdstat # Assume reboot so no process is using the dir kill %1; sync & kill %1; sync & # Force fail one too many mdadm --fail /dev/md$PRE /dev/loop${PRE}1 parallel --tag -k mdadm -E ::: /dev/loop${PRE}? | grep Upda # loop 2,5 are newest. loop1 almost newest => force add loop1 Next step is to add loop1 back - and this is where I am stuck. After that do a xfs-consistency check. When that works, check that the solution also works on real devices (such a 4 USB sticks).

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  • How to disable Skype from using system tray (notification area) on Linux?

    - by Ivan
    I use AWN dock on Linux (which behaves much like Windows 7 panes, using one icon for launching an application and managing its windows). It loses Skype (as well as any other application) when it goes minimized to system tray (notification area). Can I disable Skype from minimizing to system tray favouring Win7-like behaviour? Skype version I use is 2.1 beta, but I would not mind reinstalling it in favour of another version. I use Arch Linux with all the latest kernel, x.org and xfce.

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  • Does QEMU's performance (still) lag VirtualBox's and is there a way to improve it without kvm?

    - by Catskul
    I've noticed several articles that have claimed that QEMU is slower than VirtualBox (without hardware assistance) but several are years old, and the newest seemed to be from last year. Is it true that QEMU is slower than VirtualBox? If so why? Are there any tricks to close the performance gap? Some of my host systems do not have virtualization support so I'm especially interested in performance tips that work without the kernel module.

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  • Can a hard poweroff / outage / crash corrupt VMware snapshots?

    - by basic6
    Assuming a host system is running virtual machines (in VMware Workstation) and all their data is on a reliable storage (so no data corruption due to hdd failure). If that host crashes (kernel panic) while a vm is running, files on the virtual filesystem could be corrupted. But there's a snapshot (of the vm), taken before the crash. Is it safe to assume that reverting to the snapshot, the vm will be back in a clean state - or is there any way that this snapshot could have been corrupted by the crash?

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  • Google Chrome 20 fails to start in ubuntu 12.04

    - by criziot
    Several days ago Google Chrome stoped working after an update. If I start it in the terminal I can see the following output: [6:6:4528137750:FATAL:sandbox_init_linux.cc(378)] prctl(PR_SET_NO_NEW_PRIVS) failed: Invalid argument Any idea how to solve this? Chrome version: 20.0.1132.47 Ubuntu: 12.04 x64 Kernel: 3.2.0-21-generic #34-Ubuntu EDIT: It is possible to start chrome with --no-sandbox switch.

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  • Two network cards latency

    - by Ross W
    I'm trying to setup a network architecture where one network is a low-latency low-bandwidth tcp control system (GBit), the other is a high-bandwidth udp (maybe tcp) network that could get saturated (GBit). If I have two NICs inside a server running Linux. What happens to the low-bandwidth/low-latency network when the high-bandwidth gets saturated. Does each Ethernet card get the same amount of priority inside the kernel or would the low-latency network suffer from the high-bandwidth being saturated?

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  • HP ProLiant DL380 G3 Running Windows Server 2000 has crashed between 6-7:30am for the past 5 days

    - by user109717
    I have a HP ProLiant DL380 G3 running Windows Server 2000 that has been crashing everyday between 6-730am. This started when I changed out a failing hard drive 6 days ago. I have looked at the scheduled tasks which does not have anything pertaining to this issue. Below are the only things I see in the system log and some of the dump files. Can this be a hardware issue if this happens at a certain time frame everyday? Any help is greatly appreciated. Thanks The previous system shutdown at 6:07:55 AM on 2/7/2012 was unexpected. System Information Agent: Health: The server is operational again. The server has previously been shutdown by the Automatic Server Recovery (ASR) feature and has just become operational again. [SNMP TRAP: 6025 in CPQHLTH.MIB] BugCheck 7A, {3, c0000005, 3400028, 0} Probably caused by : memory_corruption ( nt!MiMakeSystemAddressValidPfn+42 ) Followup: MachineOwner 0: kd !analyze -v * Bugcheck Analysis * * KERNEL_DATA_INPAGE_ERROR (7a) The requested page of kernel data could not be read in. Typically caused by a bad block in the paging file or disk controller error. Also see KERNEL_STACK_INPAGE_ERROR. If the error status is 0xC000000E, 0xC000009C, 0xC000009D or 0xC0000185, it means the disk subsystem has experienced a failure. If the error status is 0xC000009A, then it means the request failed because a filesystem failed to make forward progress. Arguments: Arg1: 00000003, lock type that was held (value 1,2,3, or PTE address) Arg2: c0000005, error status (normally i/o status code) Arg3: 03400028, current process (virtual address for lock type 3, or PTE) Arg4: 00000000, virtual address that could not be in-paged (or PTE contents if arg1 is a PTE address) MODULE_NAME: nt IMAGE_NAME: memory_corruption BugCheck A, {0, 2, 1, 804137d6} Probably caused by : ntkrnlmp.exe ( nt!CcGetVirtualAddress+ba ) * Bugcheck Analysis * * IRQL_NOT_LESS_OR_EQUAL (a) An attempt was made to access a pageable (or completely invalid) address at an interrupt request level (IRQL) that is too high. This is usually caused by drivers using improper addresses. If a kernel debugger is available get the stack backtrace. Arguments: Arg1: 00000000, memory referenced Arg2: 00000002, IRQL Arg3: 00000001, bitfield : bit 0 : value 0 = read operation, 1 = write operation bit 3 : value 0 = not an execute operation, 1 = execute operation (only on chips which support this level of status) Arg4: 804137d6, address which referenced memory MODULE_NAME: nt IMAGE_NAME: ntkrnlmp.exe

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  • constantly crash on video card

    - by Jason Paddle
    I have this problem with my graphic-card(video card). Video card constantly crash because driver stopped. This is the massage that i get: Display driver stopped responding and has recovered. Display driver NVIDIA Windows Kernel Mode Driver , Version 285.62 stopped responding and has successfully recovered. Video card : MSI GTX470 Twin Frozr Motherboard:Asus P8Z68 V-Pro Tried reinstalling drivers but doesn't help. Any ideas what can be ?

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  • Ruby on Rails tutorial problem

    - by RailAddict
    Quick question which I hope is easily answered.. I am following this tutorial: http://oreilly.com/pub/a/ruby/archive/rails.html?page=2 and all is going well until I try create a controller and view it in my browser. The server is running and it shows the default page okay (http://127.0.0.1:3000). I ran ruby script\generate controller MyTest in my command line and it generated the correct folders and files. The problem is, when I go to http://127.0.0.1:3000/My%5FTest/ it says: We're sorry, but something went wrong. We've been notified about this issue and we'll take a look at it shortly. This must be something I have overlooked somewhere. Any help is appreciated! ruby 1.8.6 rails 2.3.4 Just checked my development logs. Here is what it says: /!\ FAILSAFE /!\ Thu Sep 24 02:21:04 +0100 2009 Status: 500 Internal Server Error no such file to load -- sqlite3 C:/Ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in gem_original_require' C:/Ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in require' C:/Ruby/lib/ruby/gems/1.8/gems/activesupport-2.3.4/lib/active_support/dependencies.rb:156:in require' C:/Ruby/lib/ruby/gems/1.8/gems/activesupport-2.3.4/lib/active_support/dependencies.rb:521:in new_constants_in' C:/Ruby/lib/ruby/gems/1.8/gems/activesupport-2.3.4/lib/active_support/dependencies.rb:156:in require' C:/Ruby/lib/ruby/gems/1.8/gems/activesupport-2.3.4/lib/active_support/core_ext/kernel/requires.rb:7:in require_library_or_gem' C:/Ruby/lib/ruby/gems/1.8/gems/activesupport-2.3.4/lib/active_support/core_ext/kernel/reporting.rb:11:in silence_warnings' C:/Ruby/lib/ruby/gems/1.8/gems/activesupport-2.3.4/lib/active_support/core_ext/kernel/requires.rb:5:in require_library_or_gem' C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.4/lib/active_record/connection_adapters/sqlite3_adapter.rb:10:in sqlite3_connection' C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.4/lib/active_record/connection_adapters/abstract/connection_pool.rb:223:in send' C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.4/lib/active_record/connection_adapters/abstract/connection_pool.rb:223:in new_connection' C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.4/lib/active_record/connection_adapters/abstract/connection_pool.rb:245:in checkout_new_connection' C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.4/lib/active_record/connection_adapters/abstract/connection_pool.rb:188:in checkout' C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.4/lib/active_record/connection_adapters/abstract/connection_pool.rb:184:in loop' C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.4/lib/active_record/connection_adapters/abstract/connection_pool.rb:184:in checkout' C:/Ruby/lib/ruby/1.8/monitor.rb:242:in synchronize' C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.4/lib/active_record/connection_adapters/abstract/connection_pool.rb:183:in checkout' C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.4/lib/active_record/connection_adapters/abstract/connection_pool.rb:98:in connection' C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.4/lib/active_record/connection_adapters/abstract/connection_pool.rb:326:in retrieve_connection' C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.4/lib/active_record/connection_adapters/abstract/connection_specification.rb:123:in retrieve_connection' C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.4/lib/active_record/connection_adapters/abstract/connection_specification.rb:115:in connection' C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.4/lib/active_record/query_cache.rb:9:in cache' C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.4/lib/active_record/query_cache.rb:28:in call' C:/Ruby/lib/ruby/gems/1.8/gems/activerecord-2.3.4/lib/active_record/connection_adapters/abstract/connection_pool.rb:361:in call' C:/Ruby/lib/ruby/gems/1.8/gems/rack-1.0.0/lib/rack/head.rb:9:in call' C:/Ruby/lib/ruby/gems/1.8/gems/rack-1.0.0/lib/rack/methodoverride.rb:24:in call' C:/Ruby/lib/ruby/gems/1.8/gems/actionpack-2.3.4/lib/action_controller/params_parser.rb:15:in call' C:/Ruby/lib/ruby/gems/1.8/gems/actionpack-2.3.4/lib/action_controller/session/cookie_store.rb:93:in call' C:/Ruby/lib/ruby/gems/1.8/gems/actionpack-2.3.4/lib/action_controller/failsafe.rb:26:in call' C:/Ruby/lib/ruby/gems/1.8/gems/rack-1.0.0/lib/rack/lock.rb:11:in call' C:/Ruby/lib/ruby/gems/1.8/gems/rack-1.0.0/lib/rack/lock.rb:11:in synchronize' C:/Ruby/lib/ruby/gems/1.8/gems/rack-1.0.0/lib/rack/lock.rb:11:in call' C:/Ruby/lib/ruby/gems/1.8/gems/actionpack-2.3.4/lib/action_controller/dispatcher.rb:114:in call' C:/Ruby/lib/ruby/gems/1.8/gems/actionpack-2.3.4/lib/action_controller/reloader.rb:34:in run' C:/Ruby/lib/ruby/gems/1.8/gems/actionpack-2.3.4/lib/action_controller/dispatcher.rb:108:in call' C:/Ruby/lib/ruby/gems/1.8/gems/rails-2.3.4/lib/rails/rack/static.rb:31:in call' C:/Ruby/lib/ruby/gems/1.8/gems/rack-1.0.0/lib/rack/urlmap.rb:46:in call' C:/Ruby/lib/ruby/gems/1.8/gems/rack-1.0.0/lib/rack/urlmap.rb:40:in each' C:/Ruby/lib/ruby/gems/1.8/gems/rack-1.0.0/lib/rack/urlmap.rb:40:in call' C:/Ruby/lib/ruby/gems/1.8/gems/rails-2.3.4/lib/rails/rack/log_tailer.rb:17:in call' C:/Ruby/lib/ruby/gems/1.8/gems/rack-1.0.0/lib/rack/content_length.rb:13:in call' C:/Ruby/lib/ruby/gems/1.8/gems/rack-1.0.0/lib/rack/handler/webrick.rb:46:in service' C:/Ruby/lib/ruby/1.8/webrick/httpserver.rb:104:in service' C:/Ruby/lib/ruby/1.8/webrick/httpserver.rb:65:in run' C:/Ruby/lib/ruby/1.8/webrick/server.rb:173:in start_thread' C:/Ruby/lib/ruby/1.8/webrick/server.rb:162:in start' C:/Ruby/lib/ruby/1.8/webrick/server.rb:162:in start_thread' C:/Ruby/lib/ruby/1.8/webrick/server.rb:95:in start' C:/Ruby/lib/ruby/1.8/webrick/server.rb:92:in each' C:/Ruby/lib/ruby/1.8/webrick/server.rb:92:in start' C:/Ruby/lib/ruby/1.8/webrick/server.rb:23:in start' C:/Ruby/lib/ruby/1.8/webrick/server.rb:82:in start' C:/Ruby/lib/ruby/gems/1.8/gems/rack-1.0.0/lib/rack/handler/webrick.rb:13:in run' C:/Ruby/lib/ruby/gems/1.8/gems/rails-2.3.4/lib/commands/server.rb:111 C:/Ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in gem_original_require' C:/Ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `require' script/server:3 I have no idea what this means but one thing I noticed is that it says sqlite3 - I am not using that. I am using MySql. Not sure if this is the problem..

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  • Assembly - Read next sector of a virtual disk

    - by ali
    As any programmer in the world at least once in his/her life, I am trying to create my "revolutionary", the new and only one operating system. :D Well, I am using a virtual emulator (Oracle VM Virtual Box), for which I create a new unknwon operating system, with a vmdk disk. I like vmdk because they are just plain files, so I can paste my boot-loader over the first 512 bytes of the virtual hard disk. Now, I am trying to read the next sector of this virtual disk, on which I would paste a simple kernel that would display a message. I have two questions: Am I reading the second segment (the first -512 bytes- is occupied by the bootloader) correctly? CODE: CitesteDisc: mov bx, 0x8000 ; segment mov es, bx mov bx, 0x0000 ; offset mov ah, 0x02 ; read function mov al, 0x01 ; sectors - this might be wrong, trying to read from hd mov ch, 0x00 ; cylinder mov cl, 0x02 ; sector mov dh, 0x00 ; head mov dl, 0x80 ; drive - trying to read from hd int 0x13 ; disk int mov si, ErrorMessage ; - This will display an error message jc ShowMessage jmp [es:bx] ; buffer Here, I get the error message, after checking CF. However, if I use INT 13, 1 to get last status message, AL is 0 - so no error is saved. Am I pasting my simple kernel in the correct place inside the vmdk? What I do is pasting it after the 512th byte of the file, the first 512 bytes, as I said, are the boot-loader. The file would look like this: BE 45 7C E8 16 00 EB FE B4 0E B7 00 B3 07 CD 10 <- First sector C3 AC 08 C0 74 05 E8 EF FF EB F6 C3 B4 00 B2 80 CD 13 BE 5D 7C 72 F5 BB 00 80 8E C3 BB 00 00 B4 02 B0 06 B5 00 B1 01 B6 00 B2 07 CD 13 BE 4E 7C 72 CF 26 FF 27 57 65 6C 63 6F 6D 65 21 00 52 65 61 64 69 6E 67 20 65 72 72 6F 72 21 00 52 65 73 65 74 74 69 6E 67 20 65 72 72 6F 72 21 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 55 AA <- Boot-loader signature B4 0E B0 2E CD 10 EB FE 00 00 00 00 00 00 00 00 <- Start of the second sector 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 So, this is the way I am trying to add the kernel to the second sector. What do you think is wrong with this? Thanks!

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  • What a Performance! MySQL 5.5 and InnoDB 1.1 running on Oracle Linux

    - by zeynep.koch(at)oracle.com
    The MySQL performance team in Oracle has recently completed a series of benchmarks comparing Read / Write and Read-Only performance of MySQL 5.5 with the InnoDB and MyISAM storage engines. Compared to MyISAM, InnoDB delivered 35x higher throughput on the Read / Write test and 5x higher throughput on the Read-Only test, with 90% scalability across 36 CPU cores. A full analysis of results and MySQL configuration parameters are documented in a new whitepaperIn addition to the benchmark, the new whitepaper, also includes:- A discussion of the use-cases for each storage engine- Best practices for users considering the migration of existing applications from MyISAM to InnoDB- A summary of the performance and scalability enhancements introduced with MySQL 5.5 and InnoDB 1.1.The benchmark itself was based on Sysbench, running on AMD Opteron "Magny-Cours" processors, and Oracle Linux with the Unbreakable Enterprise Kernel You can learn more about MySQL 5.5 and InnoDB 1.1 from here and download it from here to test whether you witness performance gains in your real-world applications.  By Mat Keep

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  • Toorcon14

    - by danx
    Toorcon 2012 Information Security Conference San Diego, CA, http://www.toorcon.org/ Dan Anderson, October 2012 It's almost Halloween, and we all know what that means—yes, of course, it's time for another Toorcon Conference! Toorcon is an annual conference for people interested in computer security. This includes the whole range of hackers, computer hobbyists, professionals, security consultants, press, law enforcement, prosecutors, FBI, etc. We're at Toorcon 14—see earlier blogs for some of the previous Toorcon's I've attended (back to 2003). This year's "con" was held at the Westin on Broadway in downtown San Diego, California. The following are not necessarily my views—I'm just the messenger—although I could have misquoted or misparaphrased the speakers. Also, I only reviewed some of the talks, below, which I attended and interested me. MalAndroid—the Crux of Android Infections, Aditya K. Sood Programming Weird Machines with ELF Metadata, Rebecca "bx" Shapiro Privacy at the Handset: New FCC Rules?, Valkyrie Hacking Measured Boot and UEFI, Dan Griffin You Can't Buy Security: Building the Open Source InfoSec Program, Boris Sverdlik What Journalists Want: The Investigative Reporters' Perspective on Hacking, Dave Maas & Jason Leopold Accessibility and Security, Anna Shubina Stop Patching, for Stronger PCI Compliance, Adam Brand McAfee Secure & Trustmarks — a Hacker's Best Friend, Jay James & Shane MacDougall MalAndroid—the Crux of Android Infections Aditya K. Sood, IOActive, Michigan State PhD candidate Aditya talked about Android smartphone malware. There's a lot of old Android software out there—over 50% Gingerbread (2.3.x)—and most have unpatched vulnerabilities. Of 9 Android vulnerabilities, 8 have known exploits (such as the old Gingerbread Global Object Table exploit). Android protection includes sandboxing, security scanner, app permissions, and screened Android app market. The Android permission checker has fine-grain resource control, policy enforcement. Android static analysis also includes a static analysis app checker (bouncer), and a vulnerablity checker. What security problems does Android have? User-centric security, which depends on the user to grant permission and make smart decisions. But users don't care or think about malware (the're not aware, not paranoid). All they want is functionality, extensibility, mobility Android had no "proper" encryption before Android 3.0 No built-in protection against social engineering and web tricks Alternative Android app markets are unsafe. Simply visiting some markets can infect Android Aditya classified Android Malware types as: Type A—Apps. These interact with the Android app framework. For example, a fake Netflix app. Or Android Gold Dream (game), which uploads user files stealthy manner to a remote location. Type K—Kernel. Exploits underlying Linux libraries or kernel Type H—Hybrid. These use multiple layers (app framework, libraries, kernel). These are most commonly used by Android botnets, which are popular with Chinese botnet authors What are the threats from Android malware? These incude leak info (contacts), banking fraud, corporate network attacks, malware advertising, malware "Hackivism" (the promotion of social causes. For example, promiting specific leaders of the Tunisian or Iranian revolutions. Android malware is frequently "masquerated". That is, repackaged inside a legit app with malware. To avoid detection, the hidden malware is not unwrapped until runtime. The malware payload can be hidden in, for example, PNG files. Less common are Android bootkits—there's not many around. What they do is hijack the Android init framework—alteering system programs and daemons, then deletes itself. For example, the DKF Bootkit (China). Android App Problems: no code signing! all self-signed native code execution permission sandbox — all or none alternate market places no robust Android malware detection at network level delayed patch process Programming Weird Machines with ELF Metadata Rebecca "bx" Shapiro, Dartmouth College, NH https://github.com/bx/elf-bf-tools @bxsays on twitter Definitions. "ELF" is an executable file format used in linking and loading executables (on UNIX/Linux-class machines). "Weird machine" uses undocumented computation sources (I think of them as unintended virtual machines). Some examples of "weird machines" are those that: return to weird location, does SQL injection, corrupts the heap. Bx then talked about using ELF metadata as (an uintended) "weird machine". Some ELF background: A compiler takes source code and generates a ELF object file (hello.o). A static linker makes an ELF executable from the object file. A runtime linker and loader takes ELF executable and loads and relocates it in memory. The ELF file has symbols to relocate functions and variables. ELF has two relocation tables—one at link time and another one at loading time: .rela.dyn (link time) and .dynsym (dynamic table). GOT: Global Offset Table of addresses for dynamically-linked functions. PLT: Procedure Linkage Tables—works with GOT. The memory layout of a process (not the ELF file) is, in order: program (+ heap), dynamic libraries, libc, ld.so, stack (which includes the dynamic table loaded into memory) For ELF, the "weird machine" is found and exploited in the loader. ELF can be crafted for executing viruses, by tricking runtime into executing interpreted "code" in the ELF symbol table. One can inject parasitic "code" without modifying the actual ELF code portions. Think of the ELF symbol table as an "assembly language" interpreter. It has these elements: instructions: Add, move, jump if not 0 (jnz) Think of symbol table entries as "registers" symbol table value is "contents" immediate values are constants direct values are addresses (e.g., 0xdeadbeef) move instruction: is a relocation table entry add instruction: relocation table "addend" entry jnz instruction: takes multiple relocation table entries The ELF weird machine exploits the loader by relocating relocation table entries. The loader will go on forever until told to stop. It stores state on stack at "end" and uses IFUNC table entries (containing function pointer address). The ELF weird machine, called "Brainfu*k" (BF) has: 8 instructions: pointer inc, dec, inc indirect, dec indirect, jump forward, jump backward, print. Three registers - 3 registers Bx showed example BF source code that implemented a Turing machine printing "hello, world". More interesting was the next demo, where bx modified ping. Ping runs suid as root, but quickly drops privilege. BF modified the loader to disable the library function call dropping privilege, so it remained as root. Then BF modified the ping -t argument to execute the -t filename as root. It's best to show what this modified ping does with an example: $ whoami bx $ ping localhost -t backdoor.sh # executes backdoor $ whoami root $ The modified code increased from 285948 bytes to 290209 bytes. A BF tool compiles "executable" by modifying the symbol table in an existing ELF executable. The tool modifies .dynsym and .rela.dyn table, but not code or data. Privacy at the Handset: New FCC Rules? "Valkyrie" (Christie Dudley, Santa Clara Law JD candidate) Valkyrie talked about mobile handset privacy. Some background: Senator Franken (also a comedian) became alarmed about CarrierIQ, where the carriers track their customers. Franken asked the FCC to find out what obligations carriers think they have to protect privacy. The carriers' response was that they are doing just fine with self-regulation—no worries! Carriers need to collect data, such as missed calls, to maintain network quality. But carriers also sell data for marketing. Verizon sells customer data and enables this with a narrow privacy policy (only 1 month to opt out, with difficulties). The data sold is not individually identifiable and is aggregated. But Verizon recommends, as an aggregation workaround to "recollate" data to other databases to identify customers indirectly. The FCC has regulated telephone privacy since 1934 and mobile network privacy since 2007. Also, the carriers say mobile phone privacy is a FTC responsibility (not FCC). FTC is trying to improve mobile app privacy, but FTC has no authority over carrier / customer relationships. As a side note, Apple iPhones are unique as carriers have extra control over iPhones they don't have with other smartphones. As a result iPhones may be more regulated. Who are the consumer advocates? Everyone knows EFF, but EPIC (Electrnic Privacy Info Center), although more obsecure, is more relevant. What to do? Carriers must be accountable. Opt-in and opt-out at any time. Carriers need incentive to grant users control for those who want it, by holding them liable and responsible for breeches on their clock. Location information should be added current CPNI privacy protection, and require "Pen/trap" judicial order to obtain (and would still be a lower standard than 4th Amendment). Politics are on a pro-privacy swing now, with many senators and the Whitehouse. There will probably be new regulation soon, and enforcement will be a problem, but consumers will still have some benefit. Hacking Measured Boot and UEFI Dan Griffin, JWSecure, Inc., Seattle, @JWSdan Dan talked about hacking measured UEFI boot. First some terms: UEFI is a boot technology that is replacing BIOS (has whitelisting and blacklisting). UEFI protects devices against rootkits. TPM - hardware security device to store hashs and hardware-protected keys "secure boot" can control at firmware level what boot images can boot "measured boot" OS feature that tracks hashes (from BIOS, boot loader, krnel, early drivers). "remote attestation" allows remote validation and control based on policy on a remote attestation server. Microsoft pushing TPM (Windows 8 required), but Google is not. Intel TianoCore is the only open source for UEFI. Dan has Measured Boot Tool at http://mbt.codeplex.com/ with a demo where you can also view TPM data. TPM support already on enterprise-class machines. UEFI Weaknesses. UEFI toolkits are evolving rapidly, but UEFI has weaknesses: assume user is an ally trust TPM implicitly, and attached to computer hibernate file is unprotected (disk encryption protects against this) protection migrating from hardware to firmware delays in patching and whitelist updates will UEFI really be adopted by the mainstream (smartphone hardware support, bank support, apathetic consumer support) You Can't Buy Security: Building the Open Source InfoSec Program Boris Sverdlik, ISDPodcast.com co-host Boris talked about problems typical with current security audits. "IT Security" is an oxymoron—IT exists to enable buiness, uptime, utilization, reporting, but don't care about security—IT has conflict of interest. There's no Magic Bullet ("blinky box"), no one-size-fits-all solution (e.g., Intrusion Detection Systems (IDSs)). Regulations don't make you secure. The cloud is not secure (because of shared data and admin access). Defense and pen testing is not sexy. Auditors are not solution (security not a checklist)—what's needed is experience and adaptability—need soft skills. Step 1: First thing is to Google and learn the company end-to-end before you start. Get to know the management team (not IT team), meet as many people as you can. Don't use arbitrary values such as CISSP scores. Quantitive risk assessment is a myth (e.g. AV*EF-SLE). Learn different Business Units, legal/regulatory obligations, learn the business and where the money is made, verify company is protected from script kiddies (easy), learn sensitive information (IP, internal use only), and start with low-hanging fruit (customer service reps and social engineering). Step 2: Policies. Keep policies short and relevant. Generic SANS "security" boilerplate policies don't make sense and are not followed. Focus on acceptable use, data usage, communications, physical security. Step 3: Implementation: keep it simple stupid. Open source, although useful, is not free (implementation cost). Access controls with authentication & authorization for local and remote access. MS Windows has it, otherwise use OpenLDAP, OpenIAM, etc. Application security Everyone tries to reinvent the wheel—use existing static analysis tools. Review high-risk apps and major revisions. Don't run different risk level apps on same system. Assume host/client compromised and use app-level security control. Network security VLAN != segregated because there's too many workarounds. Use explicit firwall rules, active and passive network monitoring (snort is free), disallow end user access to production environment, have a proxy instead of direct Internet access. Also, SSL certificates are not good two-factor auth and SSL does not mean "safe." Operational Controls Have change, patch, asset, & vulnerability management (OSSI is free). For change management, always review code before pushing to production For logging, have centralized security logging for business-critical systems, separate security logging from administrative/IT logging, and lock down log (as it has everything). Monitor with OSSIM (open source). Use intrusion detection, but not just to fulfill a checkbox: build rules from a whitelist perspective (snort). OSSEC has 95% of what you need. Vulnerability management is a QA function when done right: OpenVas and Seccubus are free. Security awareness The reality is users will always click everything. Build real awareness, not compliance driven checkbox, and have it integrated into the culture. Pen test by crowd sourcing—test with logging COSSP http://www.cossp.org/ - Comprehensive Open Source Security Project What Journalists Want: The Investigative Reporters' Perspective on Hacking Dave Maas, San Diego CityBeat Jason Leopold, Truthout.org The difference between hackers and investigative journalists: For hackers, the motivation varies, but method is same, technological specialties. For investigative journalists, it's about one thing—The Story, and they need broad info-gathering skills. J-School in 60 Seconds: Generic formula: Person or issue of pubic interest, new info, or angle. Generic criteria: proximity, prominence, timeliness, human interest, oddity, or consequence. Media awareness of hackers and trends: journalists becoming extremely aware of hackers with congressional debates (privacy, data breaches), demand for data-mining Journalists, use of coding and web development for Journalists, and Journalists busted for hacking (Murdock). Info gathering by investigative journalists include Public records laws. Federal Freedom of Information Act (FOIA) is good, but slow. California Public Records Act is a lot stronger. FOIA takes forever because of foot-dragging—it helps to be specific. Often need to sue (especially FBI). CPRA is faster, and requests can be vague. Dumps and leaks (a la Wikileaks) Journalists want: leads, protecting ourselves, our sources, and adapting tools for news gathering (Google hacking). Anonomity is important to whistleblowers. They want no digital footprint left behind (e.g., email, web log). They don't trust encryption, want to feel safe and secure. Whistleblower laws are very weak—there's no upside for whistleblowers—they have to be very passionate to do it. Accessibility and Security or: How I Learned to Stop Worrying and Love the Halting Problem Anna Shubina, Dartmouth College Anna talked about how accessibility and security are related. Accessibility of digital content (not real world accessibility). mostly refers to blind users and screenreaders, for our purpose. Accessibility is about parsing documents, as are many security issues. "Rich" executable content causes accessibility to fail, and often causes security to fail. For example MS Word has executable format—it's not a document exchange format—more dangerous than PDF or HTML. Accessibility is often the first and maybe only sanity check with parsing. They have no choice because someone may want to read what you write. Google, for example, is very particular about web browser you use and are bad at supporting other browsers. Uses JavaScript instead of links, often requiring mouseover to display content. PDF is a security nightmare. Executible format, embedded flash, JavaScript, etc. 15 million lines of code. Google Chrome doesn't handle PDF correctly, causing several security bugs. PDF has an accessibility checker and PDF tagging, to help with accessibility. But no PDF checker checks for incorrect tags, untagged content, or validates lists or tables. None check executable content at all. The "Halting Problem" is: can one decide whether a program will ever stop? The answer, in general, is no (Rice's theorem). The same holds true for accessibility checkers. Language-theoretic Security says complicated data formats are hard to parse and cannot be solved due to the Halting Problem. W3C Web Accessibility Guidelines: "Perceivable, Operable, Understandable, Robust" Not much help though, except for "Robust", but here's some gems: * all information should be parsable (paraphrasing) * if not parsable, cannot be converted to alternate formats * maximize compatibility in new document formats Executible webpages are bad for security and accessibility. They say it's for a better web experience. But is it necessary to stuff web pages with JavaScript for a better experience? A good example is The Drudge Report—it has hand-written HTML with no JavaScript, yet drives a lot of web traffic due to good content. A bad example is Google News—hidden scrollbars, guessing user input. Solutions: Accessibility and security problems come from same source Expose "better user experience" myth Keep your corner of Internet parsable Remember "Halting Problem"—recognize false solutions (checking and verifying tools) Stop Patching, for Stronger PCI Compliance Adam Brand, protiviti @adamrbrand, http://www.picfun.com/ Adam talked about PCI compliance for retail sales. Take an example: for PCI compliance, 50% of Brian's time (a IT guy), 960 hours/year was spent patching POSs in 850 restaurants. Often applying some patches make no sense (like fixing a browser vulnerability on a server). "Scanner worship" is overuse of vulnerability scanners—it gives a warm and fuzzy and it's simple (red or green results—fix reds). Scanners give a false sense of security. In reality, breeches from missing patches are uncommon—more common problems are: default passwords, cleartext authentication, misconfiguration (firewall ports open). Patching Myths: Myth 1: install within 30 days of patch release (but PCI §6.1 allows a "risk-based approach" instead). Myth 2: vendor decides what's critical (also PCI §6.1). But §6.2 requires user ranking of vulnerabilities instead. Myth 3: scan and rescan until it passes. But PCI §11.2.1b says this applies only to high-risk vulnerabilities. Adam says good recommendations come from NIST 800-40. Instead use sane patching and focus on what's really important. From NIST 800-40: Proactive: Use a proactive vulnerability management process: use change control, configuration management, monitor file integrity. Monitor: start with NVD and other vulnerability alerts, not scanner results. Evaluate: public-facing system? workstation? internal server? (risk rank) Decide:on action and timeline Test: pre-test patches (stability, functionality, rollback) for change control Install: notify, change control, tickets McAfee Secure & Trustmarks — a Hacker's Best Friend Jay James, Shane MacDougall, Tactical Intelligence Inc., Canada "McAfee Secure Trustmark" is a website seal marketed by McAfee. A website gets this badge if they pass their remote scanning. The problem is a removal of trustmarks act as flags that you're vulnerable. Easy to view status change by viewing McAfee list on website or on Google. "Secure TrustGuard" is similar to McAfee. Jay and Shane wrote Perl scripts to gather sites from McAfee and search engines. If their certification image changes to a 1x1 pixel image, then they are longer certified. Their scripts take deltas of scans to see what changed daily. The bottom line is change in TrustGuard status is a flag for hackers to attack your site. Entire idea of seals is silly—you're raising a flag saying if you're vulnerable.

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  • Proper Drivers for 10.10 Realtek RTL8176 Wireless and Synaptic V7.2 Touchpad Devices

    - by av7000
    I have a new Toshiba Satellite L645-S4059. This is an Intel i3 64 bit machine. Two problems have occurred that I would like to fix before transferring my work from my old compaq laptop. First I can't get the wireless driver to work properly. I went to the realtek driver site and couldn't find the 8176. Instead I was shuttled to the 8188 which uses a 8192 software release. I am not sure if the kernel is just missing the name. Second I have a synaptics V7.2 touchpad which is just flaky. It eventually freezes up so I am just using a USB mouse. Appreciate anybody's experience on this.

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  • How do I resize partitions using the simple installation wizard (installing a second Ubuntu)?

    - by d3vid
    I'm running 11.10 and installing 12.04 LTS Beta 1 off a DVD. Using the installation wizard, I picked "Install 12.04 LTS alongside 11.10". I am presented with a slider with approx 240GB on the left side and 60GB on the right. No other labels are present. I don't want to use the advanced partitioning tool. Which side is which Ubuntu? If it's relevant: I am installing only for testing purposes (I've been caught by kernel regressions before), so I want to give 12.04 the minimal amount of space required. Once the final release is made, and I've tested that too, my plan is to remove the second partition and upgrade 11.10 to 12.04.

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