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  • I want to learn to program in SDL C++where do i start? I want to learn only what i need to to start making 2d games [on hold]

    - by user2644399
    Lazyfoo of Lazyfoo.net of the SDL 2d tutorial wrote that in order for me to start game programming in SDL, I need to know these concepts well; Operators, Controls, Loops, Functions, Structures, Arrays, References, Pointers, Classes, Objects how to use a template and Bitwise and/or. I want to know the fastest way to learn as much as I need of basic c++ that would allow me to make 2d games. Thanks in advance.

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  • Stairway to T-SQL DML Level 5: The Mathematics of SQL: Part 2

    Joining tables is a crucial concept to understanding data relationships in a relational database. When you are working with your SQL Server data, you will often need to join tables to produce the results your application requires. Having a good understanding of set theory, and the mathematical operators available and how they are used to join tables will make it easier for you to retrieve the data you need from SQL Server.

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  • Harnessing PowerShell's String Comparison and List-Filtering Features

    When you are first learning PowerShell, it often seems to be an 'Alice through the looking-glass' world. Just the simple process of comparing and selecting strings can seem strangely obtuse. Michael turns the looking-glass into wonderland with his wall-chart of the PowerShell string-comparison operators and syntax The Future of SQL Server MonitoringMonitor wherever, whenever with Red Gate's SQL Monitor. See it live in action now.

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  • Google Thoughts on Website Speed

    Improving website efficiency and speeding up response time, has become increasingly important to search engines, a majority of Internet users; and in-turn, website operators. A quick website response time, to generated requests, has been proven to encourage satisfied Internet visitors; and reduce website operating costs.

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  • Showplan Operator of the Week – BookMark/Key Lookup

    Fabiano continues in his mission to describe the major Showplan Operators used by SQL Server's Query Optimiser. This week he meets a star, the Key Lookup, a stalwart performer, but most famous for its role in ill-performing queries where an index does not 'cover' the data required to execute the query. If you understand why, and in what circumstances, key lookups are slow, it helps greatly with optimising query performance.

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  • Submit to Google and Verify For Results

    Website operators should understand that successful verification does not affect their Google PageRank, or directly affect website performance; in Google's organic search results. With that being said, the data received in your Webmaster Tools, from a natural crawl of your website; is incredibly valuable to improving your SEO results.

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  • SCVMM 2012 R2 - Installing Virtual Switch Fails with Error 2916

    - by Brian M.
    So I've been attempting to teach myself SCVMM 2012 and Hyper-V Server 2012 R2, and I seem to have hit a snag. I've connected my Hyper-V Host to SCVMM 2012 successfully, and created a logical network, logical switch, and uplink port profile (which I essentially blew through with the default settings). However when I attempt to create a virtual switch on my Hyper-V host, I run into an issue. The job will use my logical network settings I created to configure the virtual switch, but when it tries to apply it to the host, it stalls and eventually fails with the following error: Error (2916) VMM is unable to complete the request. The connection to the agent vmhost1.test.loc was lost. WinRM: URL: [h**p://vmhost1.test.loc:5985], Verb: [GET], Resource: [h**p://schemas.microsoft.com/wbem/wsman/1/wmi/root/virtualization/v2/Msvm_ConcreteJob?InstanceID=2F401A71-14A2-4636-9B3E-10C0EE942D33] Unknown error (0x80338126) Recommended Action Ensure that the Windows Remote Management (WinRM) service and the VMM agent are installed and running and that a firewall is not blocking HTTP/HTTPS traffic. Ensure that VMM server is able to communicate with econ-hyperv2.econ.loc over WinRM by successfully running the following command: winrm id –r:vmhost1.test.loc This problem can also be caused by a Windows Management Instrumentation (WMI) service crash. If the server is running Windows Server 2008 R2, ensure that KB 982293 (h**p://support.microsoft.com/kb/982293) is installed on it. If the error persists, restart vmhost1.test.loc and then try the operation again. Refer to h**p://support.microsoft.com/kb/2742275 for more details. I restarted the server, and upon booting am greeted with a message stating "No active network adapters found." I load up powershell and run "Get-NetAdapter -IncludeHidden" to see what's going on, and get the following: Name InterfaceDescription ifIndex Status ---- -------------------- ------- ----- Local Area Connection* 5 WAN Miniport (PPPOE) 6 Di... Ethernet Microsoft Hyper-V Network Switch Def... 10 Local Area Connection* 1 WAN Miniport (L2TP) 2 Di... Local Area Connection* 8 WAN Miniport (Network Monitor) 9 Up Local Area Connection* 4 WAN Miniport (PPTP) 5 Di... Ethernet 2 Broadcom NetXtreme Gigabit Ethernet 13 Up Local Area Connection* 7 WAN Miniport (IPv6) 8 Up Local Area Connection* 9 Microsoft Kernel Debug Network Adapter 11 No... Local Area Connection* 3 WAN Miniport (IKEv2) 4 Di... Local Area Connection* 2 WAN Miniport (SSTP) 3 Di... vSwitch (TEST Test Swi... Hyper-V Virtual Switch Extension Ada... 17 Up Local Area Connection* 6 WAN Miniport (IP) 7 Up Now the machine is no longer visible on the network, and I don't have the slightest idea what went wrong, and more importantly how to undo the damage I caused in order to get back to where I was (save for re-installing Hyper-V Server, but I really would rather know what's going on and how to fix it)! Does anybody have any ideas? Much appreciated!

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  • LVM mirror attempt results in "Insufficient free space"

    - by MattK
    Attempting to add a disk to mirror an LVM volume on CentOS 7 always fails with "Insufficient free space: 1 extents needed, but only 0 available". Having searched for a solution, I have tried specifying disks, multiple logging options, adding 3rd log partition, but have not found a solution Not sure if I am making a rookie mistake, or there is something more subtle wrong (I am more familiar with ZFS, new to using LVM): # lvconvert -m1 centos_bi/home Insufficient free space: 1 extents needed, but only 0 available # lvconvert -m1 --corelog centos_bi/home Insufficient free space: 1 extents needed, but only 0 available # lvconvert -m1 --corelog --alloc anywhere centos_bi/home Insufficient free space: 1 extents needed, but only 0 available # lvconvert -m1 --mirrorlog mirrored --alloc anywhere centos_bi/home /dev/sda2 Insufficient free space: 1 extents needed, but only 0 available # lvconvert -m1 --corelog --alloc anywhere centos_bi/home /dev/sdi2 /dev/sda2 Insufficient free space: 1 extents needed, but only 0 available The two disks are of the same size, and have identical partition layouts via "sfdisk -d /dev/sdi part_table; sfdisk /dev/sda < part_table". The current configuration is detailed below. # pvs PV VG Fmt Attr PSize PFree /dev/sda1 centos_bi lvm2 a-- 496.00m 496.00m /dev/sda2 centos_bi lvm2 a-- 465.27g 465.27g /dev/sdi2 centos_bi lvm2 a-- 465.27g 0 # vgs VG #PV #LV #SN Attr VSize VFree centos_bi 3 3 0 wz--n- 931.02g 465.75g # lvs -a -o +devices LV VG Attr LSize Pool Origin Data% Move Log Cpy%Sync Convert Devices home centos_bi -wi-ao---- 391.64g /dev/sdi2(6050) root centos_bi -wi-ao---- 50.00g /dev/sdi2(106309) swap centos_bi -wi-ao---- 23.63g /dev/sdi2(0) # pvdisplay --- Physical volume --- PV Name /dev/sdi2 VG Name centos_bi PV Size 465.27 GiB / not usable 3.00 MiB Allocatable yes (but full) PE Size 4.00 MiB Total PE 119109 Free PE 0 Allocated PE 119109 --- Physical volume --- PV Name /dev/sda2 VG Name centos_bi PV Size 465.27 GiB / not usable 3.00 MiB Allocatable yes PE Size 4.00 MiB Total PE 119109 Free PE 119109 Allocated PE 0 --- Physical volume --- PV Name /dev/sda1 VG Name centos_bi PV Size 500.00 MiB / not usable 4.00 MiB Allocatable yes PE Size 4.00 MiB Total PE 124 Free PE 124 Allocated PE 0 # vgdisplay --- Volume group --- VG Name centos_bi System ID Format lvm2 Metadata Areas 3 Metadata Sequence No 10 VG Access read/write VG Status resizable MAX LV 0 Cur LV 3 Open LV 3 Max PV 0 Cur PV 3 Act PV 3 VG Size 931.02 GiB PE Size 4.00 MiB Total PE 238342 Alloc PE / Size 119109 / 465.27 GiB Free PE / Size 119233 / 465.75 GiB # lvdisplay --- Logical volume --- LV Path /dev/centos_bi/swap LV Name swap VG Name centos_bi LV Write Access read/write LV Creation host, time localhost, 2014-08-07 16:34:34 -0400 LV Status available # open 2 LV Size 23.63 GiB Current LE 6050 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 256 Block device 253:1 --- Logical volume --- LV Path /dev/centos_bi/home LV Name home VG Name centos_bi LV Write Access read/write LV Creation host, time localhost, 2014-08-07 16:34:35 -0400 LV Status available # open 1 LV Size 391.64 GiB Current LE 100259 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 256 Block device 253:2 --- Logical volume --- LV Path /dev/centos_bi/root LV Name root VG Name centos_bi LV Write Access read/write LV Creation host, time localhost, 2014-08-07 16:34:37 -0400 LV Status available # open 1 LV Size 50.00 GiB Current LE 12800 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 256 Block device 253:0

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  • Configuring RAID1 on HP Proliant Microserver N54L / Ubuntu 14.04.1 LTS [duplicate]

    - by Chris Beach
    This question already has an answer here: Cant find my harddrives in ubuntu installation? 2 answers I've bought a N54L and fitted two 3GB drives. Keen to get set up with RAID1. BIOS: SATA controller mode set to "RAID" RAID Option ROM utility: both physical drives set up as one logical drive When I came to install Ubuntu (14.04.1), both drives appeared during the setup process. I was only expecting to see the logical drive, although I'm a complete novice with RAID. I've read that the HP Proliant Microservers don't have "proper" RAID support, and require some kind of driver to be installed. I've tried a few HP utilities from the following apt repo: deb http://downloads.linux.hp.com/SDR/repo/mcp wheezy/current non-free On installation, most say "server not supported" Would appreciate your advice.

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  • Disk is spinning down each minute, unable to disable it

    - by lzap
    I played with spindown and APM settings of my Samsung discs and now they spin down every minute. I want to disable it, but it seems it does not accept any of the spindown time or APM values. Nothing works, it's all the same. Please help what values should be proper for it. I do not want it to spin down at all. /dev/sda: ATA device, with non-removable media Model Number: SAMSUNG HD154UI Serial Number: S1Y6J1KZ206527 Firmware Revision: 1AG01118 Standards: Used: ATA-8-ACS revision 3b Supported: 7 6 5 4 Configuration: Logical max current cylinders 16383 16383 heads 16 16 sectors/track 63 63 -- CHS current addressable sectors: 16514064 LBA user addressable sectors: 268435455 LBA48 user addressable sectors: 2930277168 Logical/Physical Sector size: 512 bytes device size with M = 1024*1024: 1430799 MBytes device size with M = 1000*1000: 1500301 MBytes (1500 GB) cache/buffer size = unknown Capabilities: LBA, IORDY(can be disabled) Queue depth: 32 Standby timer values: spec'd by Standard, no device specific minimum R/W multiple sector transfer: Max = 16 Current = 16 Advanced power management level: 60 Recommended acoustic management value: 254, current value: 0 DMA: mdma0 mdma1 mdma2 udma0 udma1 udma2 udma3 udma4 udma5 *udma6 udma7 Cycle time: min=120ns recommended=120ns PIO: pio0 pio1 pio2 pio3 pio4 Cycle time: no flow control=120ns IORDY flow control=120ns Commands/features: Enabled Supported: * SMART feature set Security Mode feature set * Power Management feature set * Write cache * Look-ahead * Host Protected Area feature set * WRITE_BUFFER command * READ_BUFFER command * NOP cmd * DOWNLOAD_MICROCODE * Advanced Power Management feature set Power-Up In Standby feature set * SET_FEATURES required to spinup after power up SET_MAX security extension Automatic Acoustic Management feature set * 48-bit Address feature set * Device Configuration Overlay feature set * Mandatory FLUSH_CACHE * FLUSH_CACHE_EXT * SMART error logging * SMART self-test Media Card Pass-Through * General Purpose Logging feature set * 64-bit World wide name * WRITE_UNCORRECTABLE_EXT command * {READ,WRITE}_DMA_EXT_GPL commands * Segmented DOWNLOAD_MICROCODE * Gen1 signaling speed (1.5Gb/s) * Gen2 signaling speed (3.0Gb/s) * Native Command Queueing (NCQ) * Host-initiated interface power management * Phy event counters * NCQ priority information DMA Setup Auto-Activate optimization Device-initiated interface power management * Software settings preservation * SMART Command Transport (SCT) feature set * SCT Long Sector Access (AC1) * SCT LBA Segment Access (AC2) * SCT Error Recovery Control (AC3) * SCT Features Control (AC4) * SCT Data Tables (AC5) Security: Master password revision code = 65534 supported not enabled not locked frozen not expired: security count supported: enhanced erase 326min for SECURITY ERASE UNIT. 326min for ENHANCED SECURITY ERASE UNIT. Logical Unit WWN Device Identifier: 50024e900300cca3 NAA : 5 IEEE OUI : 0024e9 Unique ID : 00300cca3 Checksum: correct I have the very same disc which I did not "tuned" and it does not spin. But I do not know where to read the settings from. The hdparm only shows this: Advanced power management level: 60 Recommended acoustic management value: 254, current value: 0 Edit: It seems the issue was tuned daemon in RHEL6. It was too aggressive, I turned off disc tuning and it seems they are no longer spinning down.

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  • Network monitoring tools with API features

    - by Kev
    We use ks-soft's Advanced Hostmonitor package to monitor around 2000 items on our network. We think it's great, the chap that supports it is fantastic, the product is fast, stable and mature but I feel as as we grow as a company it's beginning to show some friction points in the area of integration with our back office admin systems. One of the things we'd like to do is be able to add new tests to whatever monitoring tool we use via an API. For example, when orders for servers come from our retail interface, the server gets built automatically, and as part of the automated build process we'd like to automatically add new tests to the network monitoring systems. Hostmonitor has some support for this via a feature called HM Script but we're starting to encounter some speedbumps - we can't add new operators/users we can't define new "Action Profiles" - these are the actions to be taken when a test goes good or bad. What we love about hostmonitor though are the Action Profiles. For example if a Windows IIS box goes bad our action profile for a bad test does something like: Check host again (one time) Wait another 30 seconds then test again Try restart app pool on remote machine (up to two times) Send an email to ops about the restart failure Try restarting IIS on remote machine (up to four times) Page duty admin (up to 5 times - stops after duty admin ACKS alert) Page backup duty admin (5 times - stops after duty admin ACKS alert) I'm starting to look around at other network monitoring tools and I'm looking for: a comprehensive API to be able to add/remove/control tests/test "action profiles"/operators (not just plugins, we need control and admin interfaces) the ability to have quite detailed action/escalation profiles (and define these via an API) I've looked at Nagios and Icinga but Ican't seem to glean from their documentation whether we could have these features or not, or if we could, how much work would be involved to implement/customise. Can anyone provide any advice, guidance or experiences?

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  • LUKS with LVM, mount is not persistent after reboot

    - by linxsaga
    I have created a Logical vol and used luks to encrypt it. But while rebooting the server. I get a error message (below), therefore I would have to enter the root pass and disable the /etc/fstab entry. So mount of the LUKS partition is not persistent during reboot using LUKS. I have this setup on RHEL6 and wondering what i could be missing. I want to the LV to get be mount on reboot. Later I would want to replace it with UUID instead of the device name. Error message on reboot: "Give root password for maintenance (or type Control-D to continue):" Here are the steps from the beginning: [root@rhel6 ~]# pvcreate /dev/sdb Physical volume "/dev/sdb" successfully created [root@rhel6 ~]# vgcreate vg01 /dev/sdb Volume group "vg01" successfully created [root@rhel6 ~]# lvcreate --size 500M -n lvol1 vg01 Logical volume "lvol1" created [root@rhel6 ~]# lvdisplay --- Logical volume --- LV Name /dev/vg01/lvol1 VG Name vg01 LV UUID nX9DDe-ctqG-XCgO-2wcx-ddy4-i91Y-rZ5u91 LV Write Access read/write LV Status available # open 0 LV Size 500.00 MiB Current LE 125 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 256 Block device 253:0 [root@rhel6 ~]# cryptsetup luksFormat /dev/vg01/lvol1 WARNING! ======== This will overwrite data on /dev/vg01/lvol1 irrevocably. Are you sure? (Type uppercase yes): YES Enter LUKS passphrase: Verify passphrase: [root@rhel6 ~]# mkdir /house [root@rhel6 ~]# cryptsetup luksOpen /dev/vg01/lvol1 house Enter passphrase for /dev/vg01/lvol1: [root@rhel6 ~]# mkfs.ext4 /dev/mapper/house mke2fs 1.41.12 (17-May-2010) Filesystem label= OS type: Linux Block size=1024 (log=0) Fragment size=1024 (log=0) Stride=0 blocks, Stripe width=0 blocks 127512 inodes, 509952 blocks 25497 blocks (5.00%) reserved for the super user First data block=1 Maximum filesystem blocks=67633152 63 block groups 8192 blocks per group, 8192 fragments per group 2024 inodes per group Superblock backups stored on blocks: 8193, 24577, 40961, 57345, 73729, 204801, 221185, 401409 Writing inode tables: done Creating journal (8192 blocks): done Writing superblocks and filesystem accounting information: done This filesystem will be automatically checked every 21 mounts or 180 days, whichever comes first. Use tune2fs -c or -i to override. [root@rhel6 ~]# mount -t ext4 /dev/mapper/house /house PS: HERE I have successfully mounted: [root@rhel6 ~]# ls /house/ lost+found [root@rhel6 ~]# vim /etc/fstab -> as follow /dev/mapper/house /house ext4 defaults 1 2 [root@rhel6 ~]# vim /etc/crypttab -> entry as follows house /dev/vg01/lvol1 password [root@rhel6 ~]# mount -o remount /house [root@rhel6 ~]# ls /house/ lost+found [root@rhel6 ~]# umount /house/ [root@rhel6 ~]# mount -a -> SUCCESSFUL AGAIN [root@rhel6 ~]# ls /house/ lost+found Please let me know if I am missing anything here. Thanks in advance.

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  • “Disk /dev/xvda1 doesn't contain a valid partition table”

    - by Simpanoz
    Iam newbie to EC2 and Ubuntu 11 (EC2 Free tier Ubuntu). I have made following commands. sudo mkfs -t ext4 /dev/xvdf6 sudo mkdir /db sudo vim /etc/fstab /dev/xvdf6 /db ext4 noatime,noexec,nodiratime 0 0 sudo mount /dev/xvdf6 /db fdisk -l I got following output. Can some one guide me what I am doing wrong and how it can be rectified. Disk /dev/xvda1: 8589 MB, 8589934592 bytes 255 heads, 63 sectors/track, 1044 cylinders, total 16777216 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: 0x00000000 Disk /dev/xvda1 doesn't contain a valid partition table Disk /dev/xvdf6: 6442 MB, 6442450944 bytes 255 heads, 63 sectors/track, 783 cylinders, total 12582912 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: 0x00000000 Disk /dev/xvdf6 doesn't contain a valid partition table.

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  • Can't connect disk management to remote XP PC from local Win7/Server 2008

    - by Grez
    Scenario as follows: support technicians using Windows 7 PC's or Server 2008 terminal server are unable to connect Disk Management MMC snap in to a remote PC when the remote device is running Windows XP. "Disk management could not start Virtual Disk Service (VDS) on ". This can happen if the remote computer does not support VDS, or if a connection cannot be established because it was blocked by Windows Firewall." Connecting from another XP machine or 2003 server to the same XP machines works fine. Even connecting from XP/2003 to the Win7 or 2008 server works fine. Windows firewall disabled on all devices. I'm guessing this is something to do with the fact that XP uses logical disk manager service whereas Win7/2008 use Virtual disk manager service. But there doesn't seem to be any way to use logical disk manager service from 7/2008 to connect to XP...

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  • RAID P410i and P812 performance issues

    - by Alexey
    I'm having much trouble with I/O performance of HP DL360 server with two RAID controllers - P410i and P812, Windows Server 2008, 36 GiB RAM and 16 x Intel Xeon x5550. The server runs a bunch of tasks producing heavy sequential I/O, and after about 20-30 minutes of intensive work it looks like the tasks are stuck, not using CPU and with enough free memory (so this cannot be a bottleneck). The same tasks were running quite well on the older server (Windows Server 2003, 4 x Intel Xeon, 12 GiB RAM). RAID cache is present, write-cache battery is installed. Cache is configured as 25% readahead/75% writeback. The swap file resides on the logical disk served by P410i and other logical disks are on P812. Can someone tell me what can be the matter of this? Is this a hardware problem or misconfiguration?

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  • Server-to-Switch Trunking in Procurve switch, what does this mean?

    - by MattUebel
    I am looking to set up switch redundancy in a new datacenter environment. IEEE 802.3ad seems to be the go-to concept on this, at least when paired with a technology that gets around the "single switch" limitation for the link aggregation. Looking through the brochure for a procurve switch I see: Server-to-Switch Distributed Trunking, which allows a server to connect to two switches with one logical trunk; increases resiliency and enables load sharing in virtualized data centers http://www.procurve.com/docs/products/brochures/5400_3500%20Product%20Brochure4AA0-4236ENW.pdf I am trying to figure out how this relates to the 802.3a standard, as it seems that it would give me what I want (one server has 2 nics, each of which is connected to separate switches, together forming a single logical nic which would provide the happy redundancy we want), but I guess I am looking for someone familiar with this concept and could add to it.

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  • High I/O latency with software RAID, LUKS encrypted and LVM partitioned KVM setup

    - by aef
    I found out a performance problems with a Mumble server, which I described in a previous question are caused by an I/O latency problem of unknown origin. As I have no idea what is causing this and how to further debug it, I'm asking for your ideas on the topic. I'm running a Hetzner EX4S root server as KVM hypervisor. The server is running Debian Wheezy Beta 4 and KVM virtualisation is utilized through LibVirt. The server has two different 3TB hard drives as one of the hard drives was replaced after S.M.A.R.T. errors were reported. The first hard disk is a Seagate Barracuda XT ST33000651AS (512 bytes logical, 4096 bytes physical sector size), the other one a Seagate Barracuda 7200.14 (AF) ST3000DM001-9YN166 (512 bytes logical and physical sector size). There are two Linux software RAID1 devices. One for the unencrypted boot partition and one as container for the encrypted rest, using both hard drives. Inside the latter RAID device lies an AES encrypted LUKS container. Inside the LUKS container there is a LVM physical volume. The hypervisor's VFS is split on three logical volumes on the described LVM physical volume: one for /, one for /home and one for swap. Here is a diagram of the block device configuration stack: sda (Physical HDD) - md0 (RAID1) - md1 (RAID1) sdb (Physical HDD) - md0 (RAID1) - md1 (RAID1) md0 (Boot RAID) - ext4 (/boot) md1 (Data RAID) - LUKS container - LVM Physical volume - LVM volume hypervisor-root - LVM volume hypervisor-home - LVM volume hypervisor-swap - … (Virtual machine volumes) The guest systems (virtual machines) are mostly running Debian Wheezy Beta 4 too. We have one additional Ubuntu Precise instance. They get their block devices from the LVM physical volume, too. The volumes are accessed through Virtio drivers in native writethrough mode. The IO scheduler (elevator) on both the hypervisor and the guest system is set to deadline instead of the default cfs as that happened to be the most performant setup according to our bonnie++ test series. The I/O latency problem is experienced not only inside the guest systems but is also affecting services running on the hypervisor system itself. The setup seems complex, but I'm sure that not the basic structure causes the latency problems, as my previous server ran four years with almost the same basic setup, without any of the performance problems. On the old setup the following things were different: Debian Lenny was the OS for both hypervisor and almost all guests Xen software virtualisation (therefore no Virtio, also) no LibVirt management Different hard drives, each 1.5TB in size (one of them was a Seagate Barracuda 7200.11 ST31500341AS, the other one I can't tell anymore) We had no IPv6 connectivity Neither in the hypervisor nor in guests we had noticable I/O latency problems According the the datasheets, the current hard drives and the one of the old machine have an average latency of 4.12ms.

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  • What is "2LUN" mode in connection with RAID?

    - by naxa
    I've came across RAID products that also list JBOD (just a bunch of disks) mode and 2LUN mode. What the heck is 2LUN mode? I could not find a description; the closest thing seems to be LUN 'logical unit number' but I don't get the 2LUN thing. UPDATE 1 This is what Wikipedia has to say about JBOD: JBOD (derived from "just a bunch of disks"): an architecture involving multiple hard drives, while making them accessible either as independent hard drives, or as a combined (spanned) single logical volume with no actual RAID functionality. So JBOD can actually mean two different (albeit related) things. Answer of Guest says 2LUN means no spanning. Does this suggest that 2LUN would simply mean the JBOD-variant with no span?

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  • VMWare esxi 4.1 storage errors with MD3200

    - by Karl Katzke
    We're seeing some storage errors from the esxi logs relating to our MD3200. I'm sort of a VMWare noob and am not sure where to go from here because I couldn't find a lot of documentation on the VMWare website, and the forums didn't seem to have any posts about it with actual answers. Everything is working, but I'm trying to proactively troubleshoot this. sfcb-vmware_base|StoragePool Cannot get logical disk data from controller 0 sfcb-vmware_base|Volume Cannot get logical disk data from controller 0 sfcb-vmware_base|storelib-GetLDList-ProcessLibCommandCall failed; rval = 0x800E The ESXi boxes are connected directly via SAS to the controller on the MD3200. What do these errors actually mean, and what's a good path to start troubleshooting or solving them?

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  • Installing Solaris with Window. Disk partitioning problem.

    - by RishiPatel
    I am running windows and want to install the solaris but having hard time while using installer. I have 1 primary partition of 40GB and one extended partition. Extended partition have 4 logical drive. Solaris disk management window show only two partition one is of 40GB(Primary) and second is Extended partition. Can i convert a logical drive into primary partition( I have one free of 25 GB). Please look at the screenshot of disk management utitlity of window. http://img195.imageshack.us/img195/2005/20726948.jpg Is there any way to install solaris without reformatting the and repartitioning whole drive? In case it is not possible how should i partition and using which utility ?

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  • CentOS - Add additional hard drive raid arrays on Dell Perc 5/i card

    - by Quanano
    We have a Dell Poweredge 2900 system with Dell Perc 5/i card and 4 SAS hard drives attached, with NTFS partitions on them. We installed CentOS on one raid array on this controller with a different controller and it is working fine. We are now trying to access the drives shown above and they are not being shown in /dev as sdb, etc. sda is the drive that we installed centos on and it has sda1, sda2, sda3, etc. The CDROM has been picked up as well. If I scan for scsi devices then the perc and adaptec controllers are both found. sg0 is the CDROM and sg2 is the centos installed, however I think sg1 is the other drive but I cannot see anyway to mount the partitions, as only the drive is listed in /dev. Thanks. EXTRA INFO fdisk -l: Disk /dev/sda: 72.7 GB, 72746008576 bytes 255 heads, 63 sectors/track, 8844 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: 0x11e3119f Device Boot Start End Blocks Id System /dev/sda1 * 1 64 512000 83 Linux Partition 1 does not end on cylinder boundary. /dev/sda2 64 8845 70528000 8e Linux LVM Disk /dev/mapper/vg_lal2server-lv_root: 34.4 GB, 34431041536 bytes 255 heads, 63 sectors/track, 4186 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: 0x00000000 Disk /dev/mapper/vg_lal2server-lv_root doesn't contain a valid partition table Disk /dev/mapper/vg_lal2server-lv_swap: 21.1 GB, 21139292160 bytes 255 heads, 63 sectors/track, 2570 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: 0x00000000 Disk /dev/mapper/vg_lal2server-lv_swap doesn't contain a valid partition table Disk /dev/mapper/vg_lal2server-lv_home: 16.6 GB, 16647192576 bytes 255 heads, 63 sectors/track, 2023 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: 0x00000000 Disk /dev/mapper/vg_lal2server-lv_home doesn't contain a valid partition table These are all from the install hdd not the additional hard drives modprobe a320raid FATAL: Module a320raid not found. lsscsi -v: [0:0:0:0] cd/dvd TSSTcorp CDRWDVD TS-H492C DE02 /dev/sr0 dir: /sys/bus/scsi/devices/0:0:0:0 [/sys/devices/pci0000:00/0000:00:1f.1/host0/target0:0:0/0:0:0:0] [4:0:10:0] enclosu DP BACKPLANE 1.05 - dir: /sys/bus/scsi/devices/4:0:10:0 [/sys/devices/pci0000:00/0000:00:05.0/0000:01:00.0/0000:02:0e.0/host4/target4:0:10/4:0:10:0] [4:2:0:0] disk DELL PERC 5/i 1.03 /dev/sda dir: /sys/bus/scsi/devices/4:2:0:0 [/sys/devices/pci0000:00/0000:00:05.0/0000:01:00.0/0000:02:0e.0/host4/target4:2:0/4:2:0:0] . lsmod: Module Size Used by fuse 66285 0 des_generic 16604 0 ecb 2209 0 md4 3461 0 nls_utf8 1455 0 cifs 278370 0 autofs4 26888 4 ipt_REJECT 2383 0 ip6t_REJECT 4628 2 nf_conntrack_ipv6 8748 2 nf_defrag_ipv6 12182 1 nf_conntrack_ipv6 xt_state 1492 2 nf_conntrack 79453 2 nf_conntrack_ipv6,xt_state ip6table_filter 2889 1 ip6_tables 19458 1 ip6table_filter ipv6 322029 31 ip6t_REJECT,nf_conntrack_ipv6,nf_defrag_ipv6 bnx2 79618 0 ses 6859 0 enclosure 8395 1 ses dcdbas 9219 0 serio_raw 4818 0 sg 30124 0 iTCO_wdt 13662 0 iTCO_vendor_support 3088 1 iTCO_wdt i5000_edac 8867 0 edac_core 46773 3 i5000_edac i5k_amb 5105 0 shpchp 33482 0 ext4 364410 3 mbcache 8144 1 ext4 jbd2 88738 1 ext4 sd_mod 39488 3 crc_t10dif 1541 1 sd_mod sr_mod 16228 0 cdrom 39771 1 sr_mod megaraid_sas 77090 2 aic79xx 129492 0 scsi_transport_spi 26151 1 aic79xx pata_acpi 3701 0 ata_generic 3837 0 ata_piix 22846 0 radeon 1023359 1 ttm 70328 1 radeon drm_kms_helper 33236 1 radeon drm 230675 3 radeon,ttm,drm_kms_helper i2c_algo_bit 5762 1 radeon i2c_core 31276 4 radeon,drm_kms_helper,drm,i2c_algo_bit dm_mirror 14101 0 dm_region_hash 12170 1 dm_mirror dm_log 10122 2 dm_mirror,dm_region_hash dm_mod 81500 11 dm_mirror,dm_log blkid: /dev/sda1: UUID="bc4777d9-ae2c-4c58-96ea-cedb342b8338" TYPE="ext4" /dev/sda2: UUID="j2wRZr-Mlko-QWBR-BndC-V2uN-vdhO-iKCuYu" TYPE="LVM2_member" /dev/mapper/vg_lal2server-lv_root: UUID="9238208a-1daf-4c3c-aa9b-469f0387ebee" TYPE="ext4" /dev/mapper/vg_lal2server-lv_swap: UUID="dbefb39c-5871-4bc9-b767-1ef18f12bd3d" TYPE="swap" /dev/mapper/vg_lal2server-lv_home: UUID="ec698993-08b7-443e-84f0-9f9cb31c5da8" TYPE="ext4" dmesg shows: megaraid_sas: fw state:c0000000 megasas: fwstate:c0000000, dis_OCR=0 scsi2 : LSI SAS based MegaRAID driver scsi 2:0:0:0: Direct-Access SEAGATE ST3146855SS S527 PQ: 0 ANSI: 5 scsi 2:0:1:0: Direct-Access SEAGATE ST3146855SS S527 PQ: 0 ANSI: 5 scsi 2:0:2:0: Direct-Access SEAGATE ST3146855SS S527 PQ: 0 ANSI: 5 scsi 2:0:3:0: Direct-Access SEAGATE ST3146855SS S527 PQ: 0 ANSI: 5 scsi 2:0:4:0: Direct-Access HITACHI HUS154545VLS300 D590 PQ: 0 ANSI: 5 scsi 2:0:5:0: Direct-Access HITACHI HUS154545VLS300 D590 PQ: 0 ANSI: 5 scsi 2:0:8:0: Direct-Access FUJITSU MBA3073RC D305 PQ: 0 ANSI: 5 scsi 2:0:9:0: Direct-Access FUJITSU MBA3073RC D305 PQ: 0 ANSI: 5 i.e. the 3 RAID Arrays Seagate Hitatchi and Fujitsu hard drives respectively. FURTHER UPDATE I have installed the megaraid storage manager console and connected to the server. It appears that the two CentOS installation hard drives are OK. The other 6 drives, one raid array of 4 and one raid array of 2 disks. The other drives are listed as (Foreign) Unconfigured Good.

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  • HP Smart Array; Is it possible to convert Raid1 to Raid0 by dropping a failed drive?

    - by Erik Heppler
    I have a server that was running two 60GB drives as a logical RAID1. At some point the second drive was physically removed and the logical drive has been in "Interim Recovery Mode" for several months now. There's no need for the redundancy of RAID1 on this machine, and I have no intention of replacing the missing drive. If possible I would like to convert the current RAID1 to a single-drive RAID0 by simply dropping the failed drive from the current configuration. I'm only interested in doing this if it can be done in-place. Otherwise I'm perfectly content to leave it in "Interim Recovery Mode" indefinitely.

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