/ - rtt - IT Resource

  • hwloc-nox set CPU affinity in Linux


    sudo apt-get install  hwloc-nox Reading package lists... Done Building dependency tree       Reading state information... Done The following NEW packages will be installed:   hwloc-nox 0 upgraded, 1 newly installed, 0 to remove and 530 not upgraded. Need to get 151 kB of archives. After this operation, 453 kB of additional disk space will be used. Get:1 http://archive.ubuntu.com/ubunt........
  • gvfs mount in /run/user cannot be accessed or displayed wrong permissions


    The folder contents could not be displayed Backend currently unmounting drwx------ 10 userhere group  260 Aug 23 19:40 .. ??????????  ? ?   ?      ?            ? sftp:host=192.168.8.80,user=adhoc ls: cannot access 'sftp:host=192.168.8.80,user=adoc': Input/output error $ ps aux|grep fuse one       253........
  • VMWare ESXi 6.7 SSH/PowerShell CLI Commands


    [root@localhost:~] BootModuleConfig.sh          echo                         host-ind                     nfcd                   ........
  • VMWare Vsphere VCSA Graphical Install Creates json


    yes it does create its own json ============================================ cat /tmp/vcsaUiInstaller/ovftool-20180809-175238948-20180809-175603497.log |grep -i json 2018-08-09T17:56:04.238-07:00 verbose OVFTool[30966] [Originator@6876 sub=Default] Manifest file entry: SHA1(VMware-vCenter-Server-Appliance-6.7.0.12000-8832884_OVF10-file1.json) = 1deb658c724767697587d5909c4051c01813e6a1 -->     <ovf:File ovf:href="VMware-vCenter-Server-........
  • ./xmr-stak: error while loading shared libraries: libmicrohttpd.so.10: cannot open shared object file: No such file or directory


    The solution is just to install libmicrohttpd-dev ./xmr-stak ./xmr-stak: error while loading shared libraries: libmicrohttpd.so.10: cannot open shared object file: No such file or directory libmicrohttpd libmicrohttpd10 - library embedding HTTP server functionality libmicrohttpd-dbg - library embedding HTTP server functionality (debug) libmicrohttpd-dev - library embedding HTTP server functionality (development) $ sudo apt-get i........
  • Debian Mint Ubuntu compiling xmr-stak


    sudo apt-get install libcurl4-openssl-dev git build-essential autotools-dev autoconf libcurl3 sudo apt-get install libcurl4-gnutls-dev git clone https://github.com/wolf9466/cpuminer-multi sudo apt-get install cmake  libpthread-* libmicrohttpd-dev libssl-dev libhwloc-dev git clone https://github.com/fireice-uk/xmr-stak-cpu.git make install cd bin chmod +x xmr-stak-cpu ./xmr-stak -O xmr........
  • linux mint image convert menu option missing solution


    I already have the caja-image-converter option installed but it shows nothing. Weirdly enough if you install nemo and nautilus converter it does show and work inside caja: The solution is to install *-image-converter sudo apt-get install *-image-converter Reading package lists... Done Building dependency tree       Reading state information... Done Note, selecting 'n........
  • OVF Tool: Error: Task failed on server: This host does not support Intel VT-x. VMWare VCenter install On ESXi ERror


    Intel VT-X is enabled in Virtualbox but it doesn't seem to pass through the needed vmx extension despite the following variables on the host confirming it is enabled: cat /sys/module/kvm_intel/parameters/nested Y cat /sys/module/kvm_intel/parameters/ept Y     OVF Tool: Disk progress: 99% OVF Tool: Transfer Completed OVF Tool: Powering on VM: Embedded-vCenter-Server-Appliance- OVF Tool: Task p........
  • VMWare 6.7 VCSA VSphere ESXi Management SSO Install Guide on Linux using the CLI


    #mount the VCSA DVD mount /dev/sr0 /mnt/cd #alternatively you could mount the iso directly mount -o loop vcsa.iso /your/mount/path #for this purpose we are using the CLI installer on Linux cd /mnt/cd/vcsa-cli-installer/lin64 #no it's not going to be that easy you can't just run vcsa-deploy like that you need to use a template or configured .json file ./vcsa-deploy Usage: vcsa-deploy [-h] [--version] [--supported-deploymen........
  • Linux Mint Black Screen after boot no graphics solution


    This is not the normal "black screen" issue and I was shocked to eventually find out why.  The normal advice of reconfiguring Xorg didn't work.  Even booting into "Recovery Mode" did not help. Here is the short end of the stick that fixed it: sudo apt-get install mdm mate-desktop-environment Yes you got it right, mdm and the mate-desktop-environment / gnome were somehow uninstalled.  This must be whe........
  • Linux input/output error invalid program cannot read data on some CD-Rs and DVD-Rs on ASUS BW-16D1HT


    I've never seen this before in all of my years.  I have some very old CDs and DVDs 12-15 years old that seem not to work in this BD-R/DVD-R/CD-R Asus drive. The discs are fine actually and ironically they even work fine on a normal LG USB based BD-R drive! Here are the errors in Linux: [2914936.884924] attempt to access beyond end of device [2914936.884927] loop1: rw=0, want=730424, limit=688384 [2914954.556873] attempt to........
  • Linux How To Clone One System Harddrive to another remote system


    The easiest way is to use SSH and DD or a combination of netcat.  SSH will be a little slower due to encryption but is the most secure way (on two older systems the average clone speed is about 40-50MB/s).  This is also OS independent as it doesn't matter what the source OS is because you are literallly cloning the drive so you retain the partition table and settings.   Clone HDD using SSH and DD........
  • Linux how to copy GPT partition table with dd


    The old MBR 512 bytes partition table is no longer valid if you are using GPT.  To copy a GPT table with dd to another disk do it like so: Below sda is the source disk and destination disk is sdb (change to meet your needs). dd if=/dev/sda of=/dev/sdb bs=1536 count=1 You can also use dd to backup your partition table like normal but with the bs of 1536 dd........
  • Migrate Centos 7 from Single HDD to mdadm RAID 10 array:


    Done on Centos 7.3 very important as clearly based on older guides it was a lot easier and more simpler!  Hint do not use grub2-install! One huge caveat if you are an oldschool user or sysadmin who has avoided UEFI booting The normal way will not work here if your Centos was using UEFI.  Newer systems use it by default. The easiest way to check is to do an fdisk -l if your sy........
  • USB Device/MP3 Player not working properly and can't browse the device filesystem? Check the cable twice and again!


    Here is a simple MP3 player and now there's a reason to understand why the supplied cable has some kind of capacitor and is very short.  These devices can be VERY finicky and any voltage fluctuation or difference is enough to cause issues.   Take for example the error messages from Linux Mint: [804829.895414] usb 1-1: USB disconnect, device number 11 [806961.109030] usb 1-1: new high-speed USB device number 12 using xhci_hcd........
  • Track 01: 34 of 1726 MB written (fifo 100%) [buf 99%] 3.6x.Errno: 5 (Input/output error), write_g1 scsi sendcmd: cmd timeout after 1.897 (40) s CDB: 2A 00 00 00 44 A9 00 00 1F 00 resid: 6144 cmd finished after 1.897s timeout 40s write track da


    These errors believe it or not are simply because of not being the root user or running with sudo! However if you didn't know to try as root you'd think there was a problem with your burner or disc  Essentially it looks like without root you cannot send the required scsi commands to continue writing.  I think cdrecord should have built-in tests or safeguards to see if it has the permissions to run the required commands. I guess for more advanced users the idea is simila........
  • What happens when you unplug 1 or more devices from an mdadm RAID array to simulate a failure in Linux Ubuntu/Centos/Debian?


    In short the two drives in the array were /dev/sdd and /dev/sde.  The kernel sees they were unplugged and have gone down as you can see below. mdadm caught the first one being unplugged /dev/sde and disabled the missing drive.  However when the final drive that was part of the array is unplugged it didn't notice at all.  Instead it complains about an IO error later for drives that the kernel knows do not exist anymore. [45817.162728] ata4: exception........
  • Migrating from Linux Mint 17.2 mdadm RAID array to a new one (because I upgraded to larger drives).


    1.) Replicate the number of partitions in your new drives. gdisk /dev/sda gdisk /dev/sdb I created 3 partitions of the same same size. partition #1: +1G (/boot) partition #2: +60G (swap) partition #3: rest of it (/) #note if you are using GPT/gdisk you need to create separate a partition at least 1MB in size (in my case I would a 4th partition and mark it type ef02).........
  • mdadm: CREATE group disk not found Incrementally started RAID arrays. Incrementally starting RAID arrays...


    mdadm won't boot in Ubuntu/Mint/Debian anymore. You just get the following in a loop: mdadm: CREATE group disk not found Incrementally started RAID arrays. Incrementally starting RAID arrays... mdadm: CREATE group disk not found Incrementally started RAID arrays. Incrementally starting RAID arrays... mdadm: CREATE group disk not found Incrementally started RAID arrays. Incrementally starting RAID arrays... mdadm: CREATE group dis........
  • mdadm and lvm how to completely disable and remove vg/pv/lv


    In short the solution is just to use vgremove for the actual /dev/mapper device: vgremove /dev/mapper/backups-backuplv   box mnt # mdadm --manage /dev/md8 --stop mdadm: Cannot get exclusive access to /dev/md8:Perhaps a running process, mounted filesystem or active volume group? box mnt # lv lvchange     lvconvert    lvcreate     l........
  • mdadm frozen and doesn't realize array is dead/missing failed due to unplugged drives


    This was a surprising bug but I unplugged all drives for an array md127.  At first it was just 1 drive and mdadm seemed to notice this.  I unplugged the second drive taking the array offline but mdadm did not realize it was offline and still showed a non-existent disk as being part of it.  This created problems trying to unmount it or even to stop this array with mdadm freezing.  As for how to fix it I can only think of making sure you are not in a mounted path of........
  • fdisk wq causes hung process


    I created a new partition table on a newly plugged in device and it caused fdisk to hang (even force kill does not work).  It also may be a bad drive or some other issue because fdisk -l hangs after the first 2 HDDs (totaly of 8 HDDs on this system): [1232879.903596] INFO: task fdisk:27176 blocked for more than 120 seconds. [1232879.903607]       Tainted: P        &nbs........
  • ADATA SU800 256GB 3D NAND Flash SSD Test & Review


    I keep reading these drives are slower, but they are cheap and still SSD and work very fast for my needs. As you can see the sequential read is 481-491MB/s, if I put them in MDADM RAID10 mode (normal RAID1) they should give me well over 900MB/s and with redundancy and being very cheap for what they offer. [1232206.315622] scsi 8:0:1:0: Direct-Access     ATA      ADATA SU800   &........
  • remove gpt partition linux


    sudo fdisk /dev/sdh WARNING: GPT (GUID Partition Table) detected on '/dev/sdh'! The util fdisk doesn't support GPT. Use GNU Parted. WARNING: The size of this disk is 8.0 TB (8001563221504 bytes). DOS partition table format can not be used on drives for volumes larger than (2199023255040 bytes) for 512-byte sectors. Use parted(1) and GUID partition table format (GPT). The device presents a l........
  • /dev/drbd0: State change failed: (-2) Need access to UpToDate data solution


    Everytime I've seen this error "/dev/drbd0: State change failed: (-2) Need access to UpToDate data" it is because DRBD has no disk: cat /proc/drbd version: 8.3.13 (api:88/proto:86-96) GIT-hash: 83ca112086600faacab2f157bc5a9324f7bd7f77 build by root@sighted, 2012-10-09 12:47:51  0: cs:Connected ro:Secondary/Secondary ds:Diskless/Inconsistent A r-----     ns:0 nr:0 dw:0 dr:0 al........
  • mdadm zero-superblock to solve md device created on root device


    It is possible to tell mdadm to create an md device on a raw disk even though it will give you an error, it writes a superblock and this corrupts the partition table which can result in your system not booting. To fix it just zero the super-block on the offending device that you made the mistake in. Eg: /dev/sda mdadm --zero-superblock /dev/sda It is also a way of starting fresh if you wanted to create a new array.........
  • Linux How To Recover Partition Table from Kernel and Restore Centos/Debian etc..


    We've all done this at some point, you work on the wrong shell window and this was my first time making this mistake but I deleted a partition table in fdisk, recreated it and saved it with "wq" and even ran partprobe!  If you haven't rebooted yet then you can still recover your partition table, otherwise you're in big trouble. Fortunately since it was a live system and in use the kernel still had to use the old table like below:........
  • Linux Mint 17 How to Enable File Sharing Option in File Manager


    I still cannot understand how this would not be enabled by default and I struggled to find the reason why with manually installing samba etc.. wondering why the option for sharing was not in the menu.   On Linux Mint "MATE" the package is called "caja-share" and on Cinnamon it is called "nemo-share" so edit the below command as necessary: *Also note that the "samba" package is necessary as it is not inst........
  • VBOX/Virtualbox how to resize the disk file image vdi


    VBoxManage modifyhd "my.vdi" --resize 60000 Note the above will resize my.vdi to 60,000MB........
  • OpenVZ Error: Failed to load 2nd level quota solution


    Syncing private Live migrating container... Syncing 2nd level quota 11000: invalid option -- F Usage: vzdqload quotaid [-c file] commands Loads user/group qouta information from stdin into quota file.     -c file    use given quota file Commands specify what user/group information to load:     -G    grace time     -U    disk limits........
  • blocked for more than 120 seconds issues with iowait and timeout on Live Linux distribution while writing to physical disk


    This happened while an mdadm array was syncing, all access from writing a new blank file to opening a small .txt file was very slow:   [222117.312078] kjournald starting.  Commit interval 5 seconds [222117.685060] EXT3-fs (md0): using internal journal [222117.685096] EXT3-fs (md0): mounted filesystem with ordered data mode [222122.376847] kjournald starting.  Commit interval 5 seconds [222122.602825] EXT3-fs (md2): using internal jour........
  • Cannot load /etc/httpd/modules/mod_file_cache.so into server: /etc/httpd/modules/mod_file_cache.so:


    Stopping httpd:                                            [FAILED] Starting httpd: httpd: Syntax error on line 73 of /etc/httpd/conf/httpd.conf: Cannot load /etc/httpd/modules/mod_file_cache.so into server: /etc/httpd/modules/mod_file_cache.so: cannot open shared obje........
  • Apache SSL Reverse Proxy Very Slow Solution


    This is a simple fix but not a simple problem and it still doesn't make sense to me. But in a nutshell if your target proxy server works fast when accessing directly over SSL then this may be your issue. It seems SSL does not play nicely when the target proxy destination/host has a riduculously long key (such as 8192 bits long).  Now this is normally not a problem, in fact the target server could be accessed with hardly any delay directly despite such a long key.........
  • Error: database disk image is malformed - yum error solution and fix


    I got this when running yum on a Centos 6 machine: Error: database disk image is malformed It was easily fixed with the following command: yum clean all........
  • Errors were found while checking the disk drive for /.


    I will start by saying I think I know what caused this boot-time error on Linux Mint but should also apply to Debian and Ubuntu. I changed my BIOS time to several hours in the past to match the current time, but this caused Linux to think there were incorrect filesystem times.  The problem is that it seems when you hit this I am not sure what is happening, it doesn't seem to be doing fsck and hangs without prompting the user.  What I have found is that........
  • Is this partition table correct starting and ending partition on same cylinder?


       Device Boot      Start         End      Blocks   Id  System /dev/sdc1               1         132     1060256+  fd  Linux raid autodetect Partition 1 does not end on cylinder boundary. Partition 1 does not start........
  • Vbox Cannot register the hard disk


    Cannot register the hard disk '/media/Debian8.vdi' {d01efabc-aacf-4614-b29c} because a hard disk '/home/VirtualBox VMs/Debian/Debian8.vdi' with UUID {d01efabc-aacf-4614-b29} already exists. This is what happens if you move the VDI to another location. The easiest way is to delete/remove the machine from VBOX and then reimport it from the new location.........
  • Centos installing grub problems suspect gpt problem


    grub> root (hd0,0) root (hd0,0)  Filesystem type is ext2fs, partition type 0xfd grub> setup (hd0) setup (hd0) But if you do: root (hd1,0) setup (hd1) it does work, I think hd0/sda had a GPT partition that was not removed properly (what I did was just dd bs=512 count=1 the partition table from another drive since the partition table should be identical).  Checking if "/boot/grub/........
  • How To Record Your Screen with Linux


    Istanbul: At least in Linux Mint the latest 17.2 version Istanbul freezes when "In process of saving to Disk" even with the workaround of not having Sound recording enabled.  It looks like a great app but bugs like this seem to have plague it for over 8 years! Kazam: This little app works great, its only bug is that when you try to tell it to record a window or area it puts a gray cov........
  • How to manually mount Linux disk image partition without using losetup


    In this case we want to mount partition #2 fdisk -lu Centos-6.6-x86_64.img You must set cylinders. You can do this from the extra functions menu. Disk Centos-6.6-x86_64.img: 0 MB, 0 bytes 255 heads, 63 sectors/track, 0 cylinders, total 0 sectors Units = sectors of 1 * 512 = 512 bytes                 Device Boot &nbs........
  • bash script Get Model and Serial Number of All Hard Disks in Server on Linux


    for disk in `fdisk -l|grep "Disk /dev"|awk '{print $2}'|sed s/://g`; do echo "$disk" && smartctl -d ata -a "$disk" -T permissive|grep -iE 'Device Model:|Serial Number:' echo "---------------" done *Make sure you have smartctl from smartmon tools installed   Sample output: /dev/sdc Device Model:   ........
  • Windows showing wrong drive size after resizing the VPS/image or cloning howto fix


    1, Enter the command prompt Start -> cmd 2. Start diskpart diskpart 3. Find the drive that has the wrong size list volume 4. Select the volume (in this example we use volume 2) select volume 2 5. Extend the volume extend filesystem *Note the "exten........
  • Centos 6 how to guide convert LVM non-RAID into mdadm 1/10 RAID array live without reinstalling


    Here is the scenario you or a client have a remote machine that was installed as a standard/default minimal Centos 6.x machine on a single disk with LVM for whatever reason.  Often many people do not know how to install it to a RAID array so it is common to have this problem and why reinstall if you don't need to?  In some cases on a remote system you can't easily reinstall without physical or KVM access. So in this case you add a second physical or disk or already ha........
  • Virtualbox errors on Ubuntu/Debian/Mint


      The solution was to reinstall the vbox dkms package and do a manual modprobe of the modules it makes. I never sorted out the unable to start due to the USB issue, I did have the guest additions installed but the only way to boot was to change the pointing device from USB to PS2 and then to disable the USB controller (if your pointing device is set as USB, disabling USB will not work because it will re-enable by default when it sees your pointing device is USB, this is w........
  • How To Install Linux Mint 17.2 on mdadm RAID with a separate boot partition


    I was surprised to see that Linux Mint at the latest 17.2 version still has NO mdadm installer option, and worse the installer will not be able to create a proper booting environment even when you do install it. How to setup mdadm in Linux mint LiveCD sudo su apt-get install mdadm # partition as you need and then create your mdadm devices # create your SWAP md0 mdadm --create /dev/md0 --level=1 --raid-devices=2 /dev/sda1 /d........
  • Installing zoneminder on Ubuntu/Debian Linux Howto


    sudo apt-get install zoneminder [sudo] password for one: Reading package lists... Done Building dependency tree       Reading state information... Done The following packages were automatically installed and are no longer required:   libuser-perl python-evince kdebase-apps kwrite unixodbc   libgnomeprint2.2-data python-soappy vgabios python-metacity hddtemp   python-mediaprof........
  • grub cannot install or boot from mdadm RAID 10 array


    root (hd2,1)  Filesystem type unknown, partition type 0x83 grub> root (hd2,2) root (hd2,2)  Filesystem type is ext2fs, partition type 0x83 grub> setup (hd2) setup (hd2)  Checking if "/boot/grub/stage1" exists... no  Checking if "/grub/stage1" exists... no #weird thing about grub is that the drive you enter is considered hd0 For example when booted fu........
  • Lost connection to MySQL server during query [2013]


    This happened while trying to delete several thousand users from phpBB and basically corrupted the innoDB tables. InnoDB: Page lsn 3 881164362, low 4 bytes of lsn at page end 881164362 InnoDB: Page number (if stored to page already) 86920, InnoDB: space id (if created with >= MySQL-4.1.1 and stored already) 0 InnoDB: Page may be an index page where index id is 700 InnoDB: (index "tid_post_time" of table "phpBBdb2005"."phpbb3_p........
  • How to install grub on virtio KVM with Linux


    I messed up the bootloader by accident on a standard Centos 6.3 install because I turned the /dev/vda1 boot partition into an mdadm raid 1.  This was all done correctly aside from one point I didn't realize was an issue metadata=00.90 is the only thing that will allow you to boot (otherwise grub won't work and you won't boot). So the next step is rescue mode from a CD right? The problem you will find is that grub does not detect your hard drives, this is I believe is be........
  • KVM: unknown exit, hardware reason 0x80000021 kvm_run returned -22 solution


    If the below is happening on KVM (a very weird and scary looking error) it's probably because of Windows. This has happened countless times to me where the bootsector on Windows 7/2008 becomes corrupted easily (even by a crash or shutdown).  KVM: unknown exit, hardware reason 0x80000021 kvm_run returned -22 rax 0000000000000010 rbx 0000000000000080 rcx 0000000000000000 rdx 0000000000000080 rsi 000000000025db2a rdi 000000000007db2a rsp 0000000000000200 rbp........
  • libguestfs tools howto guide for managing virtual machine images


    libguestfs tools howto guide for managing virtual machine images To mount a partition #mount the kvmuser102821.img image and the /dev/sda1 partition from it to the local directory "mount" guestmount -a kvmuser102821.img -m /dev/sda1 mount   To list partition info on the image: virt-df image.img Filesystem          ........
  • drbd 8.3 hard drive failure recovery example


    drbd 8.3 hard drive failure recovery drbdadm attach r0 DRBD module version: 8.3.10    userland version: 8.3.8 you should upgrade your drbd tools! 0: Failure: (119) No valid meta-data signature found.     ==> Use 'drbdadm create-md res' to initialize meta-data area. <== Command 'drbdsetup 0 disk /dev/sda3 /dev/sda3 internal --set-defaults --create-device --on-io-error=call-local........
  • How to script fdisk in Linux bash


    (echo n; echo p; echo 1; echo 1; echo; echo wq) | fdisk /dev/sdb The above would make a new partition 1 on /dev/sdb and save the changes to disk, you can of course make changes to do almost anything in fdisk.........
  • Howto Convert Xen Image to KVM


    #count=10000 makes an image of 10000MB make sure your image is at least the same as your existing dd if=/dev/zero of=yourimage.img bs=1M count=10000 # losetup -fv newimage.raw # fdisk -cu /dev/loop0 # kpartx -a /dev/loop0 # dd if=<xenimage> of=/dev/mapper/loop0p1 # e2fsck -f /dev/mapper/loop0p1 # resize2fs /dev/mapper/loop0p1 # a lot of guides tell you to edit /etc/fst........
  • yum error "Error: database disk image is malformed" solution


    yum -y install mathtools Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile  * base: centos.mirror.rafal.ca  * epel: mirror.steadfast.net  * extras: mirror.agmn.ca  * rpmforge: repoforge.mirror.constant.com  * updates: centosb5.centos.org extras                         ........
  • How to view GPT/EFI Windows Partition Table


    fdisk unfortunately can't do this and I'm not sure if there's any updated version that handles it but parted can do it. Here's an example of how to do it: parted /dev/sda print 1 17.4kB 1024MB 1024MB ntfs primary 2 1024MB 16144MB 15120MB ntfs primary /dev/sda1 would be the first partiton /dev/sda2 would be the second partition You can then just access them like any other normal partition.........
  • [emerg] (28)No space left on device: Couldn't create accept lock (/etc/httpd/logs/accept.lock.15449) (5) solution


    [Wed Jan 08 18:50:07 2014] [emerg] (28)No space left on device: Couldn't create accept lock (/etc/httpd/logs/accept.lock.15449) (5) This may happen when trying to restart Apache and you find it dies right after starting and check /var/log/httpd/error_logs. What is the cause of this? You could be out of disk space (if you're not then see #2 and below) You're out of Semaphores, you need to kill all the old ones.........
  • What a hdd hard drive and mdadm RAID array failure looks like in Linux


    [3805108.257042] sd 0:0:0:0: [sda] 1953525168 512-byte hardware sectors: (1.00 TB/931 GiB) [3805108.257052] sd 0:0:0:0: [sda] Write Protect is off [3805108.257054] sd 0:0:0:0: [sda] Mode Sense: 00 3a 00 00 [3805108.257066] sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA [3805108.257083] sd 0:0:0:0: [sda] 1953525168 512-byte hardware sectors: (1.00 TB/931 GiB) [3805108.257090] sd 0:0:0:0: [sda] Write Protect is off........
  • guestmount to mount a disk image


    guestmount -a yourimage.img -m /dev/sda1 --ro /mountpoint Change "yourimage.img" to the actual disk image. Change "/dev/sda1" to the device on the disk image you want to mount. --ro is specified only if you don't want write access (good to ensure you don't mess anything up if you just want to recover data).........
  • mdadm increase recovery sync/resync speed slow solution/fix


    The units in echo are kB as in kilobyte. Setting a high sync speed echo 120000 >/proc/sys/dev/raid/speed_limit_min This will increase the speed, note that sometimes a rebuild is slow due to current disk activity/iowait. If that is not the cause then you may have a hardware issue (controller, cable or a bad drive). Setting a lower sync speed echo 1200 >/proc/sys/dev/raid/speed_limit_max........
  • Dell FS12-NV7 2U Server Information and Guide


    I've got one of these for testing projects from work at home and got more than I bargained for with the time I've spent on it due to the storage handing/Perc 6/i cards. My particular model came with the following: 2U Rack Mount Server with Rails 2xOpteron 2373 EE (Quad Core, there is a 6-core version that can be found at times) 16GB RAM 2 x 250GB Seagate SATA 2 x Dell Perc 6/i (horrible and a nightmare to work........
  • Dell Perc 6/i SATA benchmarks without battery


    The results are not bad, the Hitachi performs the same as it does in a SATA2 motherboard.  However, the 2TB is much different, on a similar 2TB Toshiba I get about 198MB/s on a different motherboard vs the 2TB Hitachi which should produce similar results. This Dell Perc 6/i is on a PCI x8 riser card and is connected to a 12-port backplane. Adapter #0     Enclosure Device ID: 32 Slot Number: 0 Enclosure position: N/A De........
  • LSI MegaRAID Adventures, Guide and HowTo


    LSi Megaraid At first it was configured as a RAID 0, then I deleted the Virtual Disk Group. I thought both drives would be shown and detected in Linux as sda and sdb but it actually shows nothing. To make them work you have to hit Ctrl+R before the system boots (when prompted) and create a Virtual Disk Group.  In my case I created each one as RAID 0 (with a single drive only) as I just wanted JBOD but there is no such option or default in these Dell Pe........
  • mkdir: cannot create directory 'test': Disk quota exceeded - Solution


    mkdir: cannot create directory 'test': Disk quota exceeded You are out of inodes usually: df -i Filesystem            Inodes   IUsed   IFree IUse% Mounted on /dev/simfs            200000  200000       0  100% / none      ........
  • qemu-img KVM create disk image howto


     qemu-img create -f qcow2 isotest.qcow2 10G The above creates a "qcow2" format image called "isotest.qcow2" that is 10GB in size.........
  • WD 20EARX Dead Again


    Another new drive bad from the start:   Jun  2 15:14:18 one-desktop kernel: [15895.386779] ata2.00: exception Emask 0x50 SAct 0x1 SErr 0x280900 action 0x6 frozen Jun  2 15:14:18 one-desktop kernel: [15895.386782] ata2.00: irq_stat 0x08000000, interface fatal error Jun  2 15:14:18 one-desktop kernel: [15895.386784] ata2: SError: { UnrecovData HostInt 10B8B BadCRC } Jun  2 15:14:18 one-desktop kernel: [15895.386788] ata2.00: cmd 60/0........
  • mdadm enable bitmap to speed up rebuilds


    Have you ever unplugged the wrong drive and then had to rebuild the entire array?  It may not be a big deal in some ways but it does make your system vulnerable until the rebuild is done. Many distros often enable the "bitmap" feature and this basically keeps track of what parts need to be resynced in the case of a temporary removal of a drive from the array, this way it only needs to sync what has changed. To enable bitmap to speed up rebuilds and sync........
  • WD 20EARX 2TB Bad within days


    This is just trying to read 5GB off the drive with dd and the drive initially tested ok but shortly after I wondered why I was seeing 2MB/s read speeds.  Notice the "current_pending_sector", anytime I've seen it at anything above 0 even with no other bad fields/attributes, it means the drive is bad. ata1.00: exception Emask 0x0 SAct 0x3 SErr 0x0 action 0x0 ata1.00: irq_stat 0x40000008 ata1.00: failed command: READ FPDMA QUEUED ata1.00: cmd 60/00:00:........
  • SMARTCTL Enable SMART on Device Solution for Error "Device does not support SMART Error Counter logging not supported"


    smartctl -a /dev/sda smartctl version 5.36 [i686-pc-linux-gnu] Copyright (C) 2002-6 Bruce Allen Home page is http://smartmontools.sourceforge.net/ Device: ATA      WDC WD1600YS-01S Version: 20.0 Serial number:      WD-WCAP03024940 Device type: disk Local Time is: Mon Apr 29 21:40:07 2013 PDT Device does not support SMART Error Counter logging not supported........
  • vzquota : (warning) block_hard_limit [102] < block_current_usage [520824] - Openvz Solution


    vzquota : (warning) block_hard_limit [102] < block_current_usage [520824] This is because your disk usage of the container exceeds the quota. Eg. once on a test container I had accidentally set it to 32MB yet the OS took about 600MB. Just set the quota to something bigger than the currently used space to solve it. vzctl set 3891 --diskspace 5G:5G --save........
  • Bad Hard Drive Slows Down Computer


    Here's a proven example of what a bad hard drive can do, it was technically functioning OK in a RAID array but the system became extremely low and the load become high and IOWAIT was even higher and I always thought it was a bad application.  The truth is that this failing 1TB Hitachi has slowly gotten worse and caused huge slowdowns, (eg. 100% load on Thunderbird waiting for e-mails to load etc..).  After swapping it out, tabs change instantly, emails are not lagged, and........
  • Samsung Galaxy Note ICS Corrupting microSDHC partition table?


    This was partitioned as a single 32GB VFAT but when I inserted it into the phone it said that it can't read it and now here is how the partition table looks.  Interestingly enough the data works and reads fine from the computer still. Disk /dev/sdb1: 32.1 GB, 32085360640 bytes 64 heads, 32 sectors/track, 30598 cylinders, total 62666720 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum........
  • How to install GRUB to the MBR of a disk image.


     cat | grub --device-map=/dev/null Now pay close to the attention of the beginning. Type: "device (hd0) VPS.img" this is telling what hd0 will be to GRUB and we're telling it the disk image file "VPS.img" in the current directory is hd0, you can specify alternate paths and image names of course.     GNU GRUB  version 0.97  (640K lower / 3072K upper memory)  [ Minimal BASH-li........
  • kvm cannot boot xen guest using lvm


    This booting error is because the Xen PV guest image uses the Xen kernel, this is not compatible with anything but a host running a Xen kernel. I did a kpartx -av virtual.img and then it created some partitions that showed up in fdisk. I mounted it and did a chroot into it and removed the xen kernel and installed a normal kernel but Xen still shows the same kernel in Grub (only the Xen one). This is strange but it seems like this Xen PV guest has some sort of hidden or........
  • Setup PXE Boot using Centos and dhcpd, tftp and syslinux


    This is something I often setup for clients because it's very helpful for people in datacenters, this allows custom OS installs on demand, you can customize it more by using kickstart etc.. but here's a base I use before customizing more: This little script below will install everything you need to get booting by PXE Linux. It also assumes you set a local IP (be sure not to overwrite your existing IP) on eth0:0 (note the :0) as 192.168.1.10 and it........
  • KVM/QEMU Base/Template Images and the power they provide


     qemu-img create -b centos.5-8.x86.20120308.qcow2 -f qcow2 ../kvmguests/25000-centos5.8x86.qcow2 Formatting '../kvmguests/25000-centos5.8x86.qcow2', fmt=qcow2, backing_file=centos.5-8.x86.20120308.qcow2, size=10485760 kB -b the source/base image -f format is qcow2 and the location of the destination image What is so special about this?  It's even quicker than creating a template with OpenVZ but this is an actual OS. It saves time a........
  • mdadm: /dev/sdb1 not large enough to join array solution


    mdadm --manage /dev/md1 --add /dev/sdb1 mdadm: metadata format 00.90 unknown, ignored. mdadm: metadata format 00.90 unknown, ignored. mdadm: metadata format 00.90 unknown, ignored. mdadm: /dev/sdb1 not large enough to join array md1's first primary member /dev/sda3 has 57394 cylinders while the /dev/sdb1 has 57393 (1 less cylinder) which is why it won't work.  fdisk -l /dev/sda3 Disk /dev/sda3: 47........
  • How to mount/access a single partition from dd image with Linux


     parted sdc.img GNU Parted 1.8.8 Using /home/one/sdc.img Welcome to GNU Parted! Type 'help' to view a list of commands. (parted) unit                                                  &nb........
  • Samsung Galaxy Note Upgrade to ICS 4.0 microSDHC card not detected/dataloss after upgrading - possible solutions


    I backed up everything in the /mnt/sd_card directory thinking that some dataloss could occur for some reason but purposely left my microSDHC unbacked up thinking that "it won't touch that since it's external" and Samsung's and other manufacturers website even say this (that it won't be affected and not to worry etc). Apparently I was wrong, my microSD was "undetected" and asked to be formatted after the upgrade (there goes 3-months worth of family photos).  No........
  • xen how to resize an image properly


    The best way I could figure out is to use another guest of some sort to do this, while assigning the disk that needs to be resized to the same guest. So say we have /dev/xvda as the guests drive and we've booted it up. We also have /dev/xvdb (this is going to be the image/disk to be resized). In this case it's based on an ext3/4 image. Run e2fsck on it to ensure there are no filesystem errors. e2fsck /dev/xvdb........
  • How to view an EFI GPT partition in Linux


    Disk /dev/sda: 320.0 GB, 320072933376 bytes 256 heads, 63 sectors/track, 38761 cylinders Units = cylinders of 16128 * 512 = 8257536 bytes    Device Boot      Start         End      Blocks   Id  System /dev/sda1               1       38........
  • Debian UUID not working


    Neither the blkid or the UUID internal to mdadm work to automount for some reason in Debian partprobe doesn't work but was a good suggestion from: http://pato.dudits.net/2008/11/03/special-device-uuidxxxxxxxxxxxxxxxx-does-not-exist-especially-with-lvm mount: special device /dev/disk/by-uuid/431b9b96-29e8f298-e89bd504-7065bddd does not exist mdadm -D /dev/md_d12 mdadm: metadata format 00.90 unknown, ignored. /dev/md_d12:   &nb........
  • Windows Secret Hidden Temp Directory to free out of disk space issues


    Replace "Administrator" with your username. C:Documents and SettingsAdministratorLocal SettingsTemp I have often found several gigabytes of temporary files in there!  Just be warned that they may not all be deletable if the files are being used by open programs (so close everything you can). This helped me in a pinch many times when for apparently no reason gigs of disk space are being used for an unknown reason.........
  • Xen how to mount disk images off-line and access data


    fdisk -lu VPS.img last_lba(): I don't know how to handle files with mode 81ed You must set cylinders. You can do this from the extra functions menu. Disk VPS.img: 0 MB, 0 bytes 255 heads, 63 sectors/track, 0 cylinders, total 0 sectors Units = sectors of 1 * 512 = 512 bytes      Device Boot      Start         End   ........
  • Ubuntu 10 Nvidia Drivers Not Updated After Kernel Update Solution/How-To Manually Rebuild nvidia kernel modules for Ubuntu


    I dread updating the kernel and rebooting to find the Ubuntu graphics aren't working and you have to manually intervene.   This is usually because Ubuntu for whatever reason didn't update the drivers you need (eg. the manually compiled Nvidia Kernel driver that MUST be recompiled for each and every kernel update unfortunately). The most common reason may be that "linux-source" hasn't been installed automatically on my system.  I tried to manually reinstall the........
  • How To Burn ISO Image using cdrtools/dvdrtools for Linux/Unix Ubuntu/Debian/RHEL/Centos etc..


    It really is as simple as: cdrecord -v dev=/dev/sr0 pathtoyourisoimage.iso -v is for verbose, I prefer it but if you don't you won't see as much output like below (I like to know the details and exactly what's happening) dev=/dev/sr0 specifies the device name of your burner (they say not to use it and to specify some weird annoying device string but using the raw /dev has always worked for me and is how it should have been implemented from the start IMHO)........
  • Ubuntu Suspend Solution Fix blank screen laptop/computer won't come back


    Even in new versions of Ubuntu this happens but for me I found out it was because of one feature under "Power Management". I had "Spindown hard disks when possible" ticked, after disabling that, my computer wakes up from suspension every time now.  So if your computer won't unsuspend with any version of Ubuntu/*Nix try disabling the spin down hard disk option as it's obviously the culprit for many situations.........
  • Hitachi HDD/Drive RMA Process Experience


    The first Hitachi Deskstar 2TB 5K3000 drive I bought arrived DOA for whatever reason (not recognized by the BIOS or OS).  Perhaps it was shipping since I bought only 1 hard drive.  When I bought 4 through another Vendor, all 4 checked out fine. I was worried about the RMA process because a lot of people have complained about Hitachi taking weeks to send out their hard drive and almost implied the warranty is useless. I'm happy to report that my experience was great a........
  • How To Test If Your Hard Drive Is Good/Signs of dying hard drive


    I like dd, although it only reads it, usually a read test of the entire disk will uncover if your hard drive is bad in some parts.  This is a good thing to do at least once a month, a lot of times bizarre program behavior, laginess and crashing/unnmounting problems etc.. are due to a failing disc and SMART won't know it or indicate a problem: We must also remember there's never a guarantee, I've found that ever since we moved to larger and more platters per drive with 1TB drives........
  • smart is not smart, it thinks a dead drive is still good


    I had a dying drive that smart thought until it totally disappeared was a good drive, and actually all parameters did look fine but this system was causing my system to lockup and other bad behavior:   === START OF INFORMATION SECTION === Device Model:     WDC WD20EARS-00MVWB0 Serial Number:    WD-WMAZ20139 Firmware Version: 50.0AB50 User Capacity:    2,000,398,934,016 bytes Device........
  • Hitachi 2TB HDS5C3020ALA632 drive DOA


    I had one of these shipped and it was not recognized when plugged in, here's what a dead drive looks like (I assume it's teh circuit board which is dead):   ata1: link is slow to respond, please be patient (ready=0) ata1: softreset failed (device not ready) ata1: SATA link up 3.0 Gbps (SStatus 123 SControl 300) ata1: link online but device misclassified, retrying ata1: link is slow to respond, please be patient (ready=0) ata1: softreset f........
  • How to recover from dead DRBD partition/hard drive in two simple commands


    This assumes that you've at least created the correct partition for your DRBD already. Notice that I am "diskless", that's because either your DRBD partition doesn't exist/has been renamed (eg. sdb becomes sda when sdb dies and you reboot) or because that drive is really actually dead/gone. *If you need to permanently change the partition/device for your resource be sure to edit /etc/drbd.conf on both hosts and reload the config. (replace r0 with........
  • Kernel/make compilation time and how to improve compile times/compile the Linux kernel faster without hardware upgrades


    I thought only a faster CPU and SSD would help but I already have a Quad-Core CPU and it wasn't being maxed out.  The actual tests were performed on an AMD-V enabled 128MB dual core VMWare container though. There is a flag that can be passed to make in order to start multiple threads, by specifying 4 threads I was able to reduce the whole kernel compilation time from scratch by about 50%! (65minutes vs 31minutes!).  *Yes I did do a make clean before each co........
  • VBox/Virtualbox how to shrink VDI image and recover/reclaim unused disk space


    VBoxManage modifyvdi /path/to/your.vdi compact I believe this should be done only when your VM is powered off, but I decided to try it with the system powered on.  i wouldn't recommend it because it's dangerous even if it does work but this is a test system.  For anything important/production I would always take a backup first and make sure the system is powered off.  VBoxManage modifyvdi XP-clone.vdi compact 0%...10%...20%...30%...40%...5........
  • iPhone 3G/3GS/4 Undelete Photos/Videos Datarecovery


    I found this technique listed in many places which shows you how to use a common Linux tool "dd" to dump the raw partition of your iPhone. I give credit to this site for showing me the correct way to dd from the iPhone, I never thought to try it in the other direction: http://log.ijulien.com/post/182804914/iphone-3gs-data-recovery Requirements 1.) Jailbreak your........
  • Are my WDEARS20 Drives dying already?


    This happened during a RAID array check: SMART says both drives pass the test, but I'm doing a long test on them and hopefully this is not a hardware error. Apr  3 04:22:01 remote kernel: md: syncing RAID array md2 Apr  3 04:22:01 remote kernel: md: minimum _guaranteed_ reconstruction speed: 1000 KB/sec/disc. Apr  3 04:22:01 remote kernel: md: using maximum available idle IO bandwidth (but not more than 200000 KB/sec) for reconstruction. Apr........
  • CPU #1 not responding - cannot use it.


    I think this will be useful to others because I have a server that kept crashing mysteriously during intense disk usage/RAID checks.  It would only crash during the weekly RAID integrity check. Then I noticed during a reboot that not all CPUs were being brought up, as a result this actually creates much higher temperatures with the output I got from sensors, just booting the system produced higher than normal temperatures. You can imagine that a full blown RAID check........
  • Openvz Disk quota exceeded inode problem with free space


    Openvz problem, it is confusing because it's an inode issue and there is enough free space. cp: cannot create regular file `forums/memberlist.php': Disk quota exceeded /dev/simfs             60G   20G   41G  33% / none                  2.0G  4.0K  2.0G   1% /dev........
  • updatedb/mdadm caused a kernel panic?


    Jan 16 04:02:03 centosbox syslogd 1.4.1: restart. Jan 16 04:07:34 centosbox kernel: INFO: task updatedb:20771 blocked for more than 300 seconds. Jan 16 04:07:34 centosbox kernel: "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. Jan 16 04:07:34 centosbox kernel: updatedb      D F78BE050  6476 20771  20766                &n........
  • ERROR! MySQL manager or server PID file could not be found! ERROR! Manager of pid-file quit without updating file.


    I found the cause of this issue was from all the diskspace being used but clearing it was not enough.  I guess the tables became inconsistent when space ran out and myisamchk is what fixed the rest.   service mysqld restart ERROR! MySQL manager or server PID file could not be found! ....................................................................................... ERROR! Manager of pid-file quit without updating file. se........
  • mdadm/md-check how to check array integrity without rebuilding


    This doesn't seem to be widely known (maybe it's in some documentation that none of us read though) but there's an easy way to check the integrity of any mdadm array: sudo echo check > /sys/block/md0/md/sync_action -bash: /sys/block/md0/md/sync_action: Permission denied sudo will never work, this only works as root since echo is not actually a binary/command.  It is built-into bash. /sys/devices/virtu........
  • md: data-check of RAID array md3


    This really made me nervous but notice the mdstat says "check".  This is because in Ubuntu there is a scheduled mdadm cronscript that runs everyday on Sunday at 00:57 that checks your entire array.  This is a good way because it prevents gradual but unnoticed data corruption which I never thought of. As long as the check completes properly you have peace of mind knowing that your data integretiy is assured and that your hard drives are functioning properly (I'........
  • WD EARS Advanced Format Can't be fixed?


    There's no partial WD EARS alignment fix: I had data on /dev/sda3 and /dev/sdb3 (RAID1) so I couldn't edit that one. I thought I'd be smart and try fixing the first two partitions so I set the first one starting at sector 2048 and then +8 for the second partition. This has really slowed the performance down worse than it ever was! Disk /dev/sda: 2000.4 GB, 2000398934016 bytes 255 heads, 63 sectors/track, 243201 cylinders, tot........
  • vmare server - Cannot open the disk '/mnt/sda4/vmware/Debian/hdd.vmdk' or one of the snapshot disks it depends on. Reason: Failed to lock the file.


    Go into the directory for your Virtual Machine and delete all ".lck" directories. rm -rf *.lck After that your server should boot.........
  • Ubuntu/Debian DRBD 8.0 Setup Guide


    I've only used it on Centos, so I thought I'd make a quick Debian guide: Install the DRBD Package apt-get install drbd8-utils Reading package lists... Done Building dependency tree       Reading state information... Done The following packages were automatically installed and are no longer required:   libswfdec-0.8-0 Use 'apt-get autoremove' to remove them. The following........
  • VirtualBox Convert Import/Boot .vmdk VMWare Hard Disk/Drive Image Won't Work


    I wanted to Import/Use a .vmdk hard disk image file from VMWare.  Generally you can just "point" VirtualBox to it and use it and it will work but I found an exception. One of my Centos 4.4 x64 images wouldn't boot.  I had two copies, an older one and the newer one.  The older one booted as normal (once I changed the VirtualBox driver to IDE from SATA).  The newer one stopped at the "GRUB loading" message no matter what I tried. As far as........
  • vzquota : (warning) Incorrect quota shutdown for id 2333, recalculating disk usage vzquota : (error) quota check : lstat `sess_a5078fce5f569e453ab1fb39b0fc69f8': No such file or directory vzquota on failed [1]


    first container would not come up: Starting CT 2333: service vz stop OpenVZ is locked                                           [FAILED] 2010-11-29T23:26:23-0800 vzctl : CT 2333 : Starting container ... 2010-11-29T23:37:21-08........
  • WD EARS/Green 2TB Cannot Disable Power Saving/Head Parking with hdparm


    hdparm -B 255 /dev/sdb /dev/sdb:  setting Advanced Power Management level to disabled  HDIO_DRIVE_CMD failed: Input/output error   The one thing you can do though is to set hdparm spindown time lower (it doesn't seem to work that well).  -S   set standby (spindown) timeout   hdparm -S 251 /dev/sda /dev/sda:  setti........
  • mdadm RAID 1 adventures


    I separated the 2 drives in the RAID 1 array. 1 is the old one /dev/sda and is out of date, while the separated other one /dev/sdc was in another drive and mounted and used with more data (updated). I wonder how mdadm will handle this: usb-storage: device scan complete md: md127 stopped. md: bind<sda3> md: md127: raid array is not clean -- starting background reconstruction raid1: raid set md127 active with 1 out of 2 m........
  • WD (Western Digital) Advanced Format Drive Lagged/Slow Speed/Performance/Design Flaw EAD/EARS problem WDC WD20EARS-00S8B1


    Let the numbers speak for themselves, from what I read the Load_Cycle_Count which is very high (more than 500,000/half a million times) is the number of head parks.  What a stupid "Green" design and design flaw which will probably mean an early life for the drive. This is almost as silly as Seagate's new reputation for BSY/poor quality disks since the 7200.11 series. To make it worse this is also when Western Digital introduced "Advanced Format" o........
  • Ubuntu 10.04/GRUB2 mdadm won't boot


    Moving to RAID was a pain. What you have to do is the following from an existing install: Install mdadm Create your mdadm RAID 1 array on your spare hard drive. Start it with the missing disk. rsync the entire contents of your current / to the md partition. Here's a good way of doing it: rsync -Pha --exclude=/proc/* --exclude=/sys/* --exclude=/mnt/* /. /mnt/md2........
  • Wine stopped working/won't work Solution


    After an upgrade wine wouldn't open anything, not even the pre-installed notepad. There are no wine logs and nothing is mentioned in any standard log file about why. I finally decided to run wine from the shell and see what's going on: wine client error:0: version mismatch 398/402. Your wineserver binary was not upgraded correctly, or you have an older one somewhere in your PATH. Or maybe the wrong wineserver is still running?........
  • Buffer I/O error on device fd0, logical block 0


    Virtually no system has a floppy disk drive anymore but you will often find your Linux distribution insists that you do or should have one :) The solution is to remove the floppy module and prevent it from loading on the next reboot. rmmod floppy Centos/RHEL echo "blacklist floppy" >> /etc/modprobe.d/blacklist Debian/Ubuntu sudo echo "blackli........
  • Initializing quota ... Error: Not enough parameters, diskinodes quota not set


    Initializing quota ... Error: Not enough parameters, diskinodes quota not set vzctl set $veid --diskinodes 90000:91000 --save   New versions of OpenVZ seem to have some strange diskinodes parameter which is required.........
  • SolusVM/Xen Central Backup Warning - Takes System Off-line!


    This really gives me a bad impression of SolusVM. I tried the "Central Backup" option and it does not warn that your server gets shutdown instantly in order to do the backup! Further, there is no way to pause or cancel the backup.  Thankfully this is a test/small disk usage VPS but what if someone was running something production with a large filesize? I haven't used QuickBackup but hope that isn't the same thing. Everyone should be vary car........
  • DRBD WFConnection Problem/Solution


    This has stumped me  a few times because I keep forgetting that Centos 5.5 comes with a default iptables configuration that ends up blocking DRBD traffic, I tried all the normal things and couldn't understand why I couldn't make my normal DRBD config work.  So if you have WFConnection problems and have tried the normal "mailing list" fixes, check your firewall status first! Both Nodes Say the Following: version: 8.3.8 (api:88/prot........
  • VirtualBox Error Failed to start the virtual machine Centos 5.5 Mirror. Medium '/home/testuser/.VirtualBox/HardDisks/Centos 5.5 Mirror.vdi' is not accessible. UUID {a1a9fad7-0402-4867-b8f3-39fb49454bc5} of the medium '/home/testuser/.VirtualBox/HardD


    Virtualbox Error I tried to copy a .vdi of one container to use in another one, basically to clone instead of having to install the OS again. Failed to start the virtual machine Centos 5.5 Mirror. Medium '/home/testuser/.VirtualBox/HardDisks/Centos 5.5 Mirror.vdi' is not accessible. UUID {a1a9fad7-0402-4867-b8f3-39fb49454bc5} of the medium '/home/testuser/.VirtualBox/HardDisks/Centos 5.5 Mirror.vdi' does not match the value {4945a0e8-0ed5-4736-9088-bcaf........
  • md: kicking non-fresh sda1 from array! - fix/solution


    md: Autodetecting RAID arrays. md: autorun ... md: considering sdb1 ... md:  adding sdb1 ... md:  adding sda1 ... md: created md0 md: bind<sda1> md: bind<sdb1> md: running: <sdb1><sda1> md: kicking non-fresh sda1 from array! md: unbind<sda1> md: export_rdev(sda1) raid1: raid set md0 active with 1 out of 2 mirrors The md0 raid kicked sda1 ou........
  • Install Mac OS X 10.4.6 Tiger on AMD32 VMWare


    *Note OS X is strange to install, I thought my HDD was not being detected by you just have to go to Diskutil and create a partition for the root filesystem and then close/move the Window and proceed with the install. After install Mac OS X 10.4.6 Tiger I get a black screen that says: b0 error Most people say the partition has to be marked as "active", actually that just means marked as "bootable".  Instead of t........
  • Use rcconf to edit startup/init.d/init scripts on Debian/Ubuntu based distributions


    I've never understood how to enable and disable services for different run levels in Debian based distros, it's just weird, annoying and doesn't make sense.  I much prefer chkconfig from RHEL. Just install the package called 'rcconf' and be done with it.  rcconf makes things easy for you. apt-get install rcconf Reading package lists... Done Building dependency tree        Reading state information... Done........
  • mdadm: /dev/sda1 is too small: 0K - solution


    I was creating a RAID array and got this error: mdadm: /dev/sda1 is too small: 0K mdadm: create aborted Of course sda1 is not too small, both partitions sda1 and sdb1 are identical in size: Disk /dev/sda: 2000.3 GB, 2000398934016 bytes 255 heads, 63 sectors/track, 243201 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Disk identifier: 0x00000000    Device Boot      Sta........
  • Unixbench Score on Core i5 750 with OpenVZ Kernel vs Xen/Openvz


    This was unbelievable how much the Xen kernel slows things down, keep in mind both tests were done on the hostnode, one was with the Openvz-Xen hybrid kernel and the other was just OpenVZ.  You can see the performance difference is nearly 300% better when not using the Xen kernel. OpenVZ-Xen Kernel Test Results (I was wondering what was wrong/so slow with my Core i5!)    #    #  #    #  #  #  &n........
  • chroot into an off-line Linux version using a LiveCD/USB


    It's not just as simple as running the chroot command, you need to ensure the /proc and /dev entries are passed through and populated to the chroot environment. Step 1 - Mount Your Off-line OS mount /dev/sda1 /mnt Step 2 - Mount Proc mount -t proc none /mnt/proc Step 3 - Mount Dev Most guides will tell you to use this: mount -o bind /dev /mnt//dev but that doesn't work for some reason in many cases: mount: wron........
  • Seagate Drive 500GB Drive Dying


    This drive is clearly on the way out, the Kernel knows it but I'm surprised that SMART is not concerned.  I didn't blame Seagate for their past issues until now.  This hard drive has hardly been used and has not even been powered on for a year according to SMART. Home page is http://smartmontools.sourceforge.net/ === START OF INFORMATION SECTION === Model Family:     Seagate Barracuda 7200.11 Device........
  • Seagate 7200.11 firmware defect in 500GB, 1000GB (1TB) and 1500GB (1.5TB) Hard Drives


    Seagate Inventory/Firmware Check I heard about this issue a long time ago but never looked into it.  I figured I wasn't affected since my 500GB drives were running for so long.  I've been using Seagate's since 2002 and to this day all of the drives I have are alive from Seagate. *Update the bad news is that I realize one of my 500GB's is about to die, it's not even a year old, but is also not affected by the recall according to Seagate! Seagate Inventory/Firm........
  • Linux AHCI Hotswap Tips - Remember To Reread The Partition Table WITHOUT rebooting


    From the package "parted" you can use the command "partprobe" to re-read the partition table.  I really hate rebooting, and that's what I loved to hear about AHCI motherboards, that they allow hotswap so you don't have to reboot.  But that's only as good as the OS, if the OS does not reload the partition table you won't be able to do anything with that new drive you attached without rebooting.  Yes, even without re-reading the partiton table Linux will........
  • Convert HDD/Hard Drive Partition(s) into non-RAID into RAID 1 using existing data without data loss and without reformatting.


    Before we start I take no responsibility for this, you should have a backup and if you make a mistake during this process you could wipe out all of your data.  So backup somewhere else before starting this as a precaution, or make sure it's data you could afford to lose. The RAID 1 Setup (Hardware Wise) I've already setup my 2 x 1TB (Seagate) drives with identical partitions, make sure your new hard drive (the empty one) is setup like your curr........
  • Monitor MB/s Disk IO Usage/Bandwidth - Use iostat from the sysstat Package


    The binary "iostat" comes from the package "sysstat" and is available on all Linux/Unix like platforms.  Use the "-m" option to give you what you probably want, which is to see in MB/s how much bandwidth each disk is doing. iostat -m Linux 2.6.24.2 ((none))         04/16/10 avg-cpu:  %user   %nice %system %iowait  %steal   %idle   ........
  • Linux EXT3 16GB-17GB maximum filesize issue solved/how to fix


    I have no idea why but mkfs.ext3 defaults to a patheticlly small blocksize of 1024 bytes/1KB (kilobyte).  That means the maximum filesize is ONLY 16GB!  With 2KB/2048 bytes you get a 256 GB maximum filesize, and with 4KB/4096 bytes you get 2TB! I finally noticed/paid attention to this after realizing that with rsync and scp that no file larger than 17GB could be transferred.  I then realized it must be a file size limit on the partition. Here is what tune2fs tol........
  • Rsync Timeout/Stall On Large files bigger than 16GB/Cannot Transfer large files with rysnc


    The last transfer I was able to do was 16.77GB according to rsync's output and it worked fine.        16.77G 100%   10.66MB/s    0:25:00 (xfer#17484, to-check=234753/256249) But on a file over 17GB (gigs) it stalls.  Trust me, it really is stalled, it's been about 8 hours with no progression from that point for some reason. 17.24G  54%   10.65MB/s    0:22:07........
  • XMPP Chat Protocol using Jabber - Guide Tutorial Setup Linux Chat Server


    In Debian based distros: apt-get install jabber Reading package lists... Done Building dependency tree       Reading state information... Done The following packages were automatically installed and are no longer required:   fakeroot dkms Use 'apt-get autoremove' to remove them. The following extra packages will be installed:   jabber-common The following NEW packag........
  • Picking an FTPD (vsftpd) Server in Linux Centos/Debian


    I decided on using yum to help me decide even though I normaly use proftpd I decided to see what else I could find. yum search ftp Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile  * rpmforge: ftp-stud.fht-esslingen.de  * base: mirrors.netdna.com  * updates: updates.interworx.info  * addons: yum.singlehop.com  * extras: mirrors.netdna.com rpmforge   ........
  • ntfs-3g Error/Fix/Solution - Unexpected sectors per cluster value (127). Failed to mount '/dev/sda1': Invalid argument The device '/dev/sda1' doesn't seem to have a valid NTFS. Maybe the wrong device is used? Or the whole disk instead of a


    ./ntfs-3g /dev/sda1 /mnt -o force Unexpected sectors per cluster value (127). Failed to mount '/dev/sda1': Invalid argument The device '/dev/sda1' doesn't seem to have a valid NTFS. Maybe the wrong device is used? Or the whole disk instead of a partition (e.g. /dev/sda, not /dev/sda1)? Or the other way around? This is happening on a system I've come across an HP 6930P running Windows XP Professional.  The partition appears to be very norm........
  • Compaq V2405CA Laptop - Unixbench Performance Test


    Here are the results, it is Sempron 3000+ AMD Mobile, 500Gig HDD, 512MB RAM with shared ATI Radeon graphics.      #    #  #    #  #  #    #          #####   ######  #    #   ####   #    #    #    #  ##   #  #   #  #&nb........
  • heartbeat is stopped for some reason


    heartbeat is stopped for some reason Anyway hnode2 was active and the services are running fine but I see heartbeat has been stopped somehow. Here is the last log I see of heartbeat: [quote:23c84415f5] Sep 9 17:15:32 hnode2 heartbeat: [16738]: info: MSG stats: 9/1762471 ms age 0 [pid16738/MST_CONTROL] Sep 9 17:15:32 hnode2 heartbeat: [16738]: info: cl_malloc stats: 716/51784021 152624/74519 [pid16738/MST_CONTROL] Sep 9 17:15:32........
  • rsync bash script


    rsync bash script [code:1:722d8a25c1]#!/bin/bash # config --------------------------------- # two methods # from = receive data from another server # to = send data to another server rsync_method=from rsync_ip='192.168.5.18' local_dir='/home/backupguy/backups' remote_dir='/home/backup' free_space_bin='/home/backups/freediskspace.sh' # config end ------------------------------ if [ '$rsync_me........
  • Clone any OS partition perfectly


    Clone any OS partition perfectlyIn one box I needed to copy the boot partition to another disk while retaining the MBR and other data. I simply ran this command: [code:1:1b1ff110ca]dd if=/dev/hda1 of=/dev/hdb1[/code:1:1b1ff110ca] [b:1b1ff110ca]if[/b:1b1ff110ca] = source patition [b:1b1ff110ca]of[/b:1b1ff110ca] = destination partition Here's an interesting article on it http://www.rajeevnet.com/hacks_hints/os_cl........
  • Mount Linux ext2 file system


    Mount Linux ext2 file systemNormally in Linux you could mount ext2 or ext3 etc... like this: mount -t ext2 /dev/hda1 /mnt/hda1/ In FreeBSD the difference is of course the disk naming conventions (hda1 would be known a /dev/ad0s1): To mount ext2 in FreeBSD just type: mount -t ext2[b:68c16c60bf]fs[/b:68c16c60bf] /dev/ad0s1 /mnt/ad0s1........
  • The New Chips on the Block


    The New Chips on the BlockThe New Chips on the Block By Bruce Gain Story location: http://www.wired.com/news/infostructure/0,1377,67795,00.html 02:00 AM Jun. 13, 2005 PT We have embarked upon a new era in x86 PC computing -- so say chip giants AMD and Intel following their launches of dual-core PC processors. So how will dual-core processing change your PC computing experience? Our FAQ should help you decide whether or when you sho........
  • 100% disk usage for no apparent reason!


    100% disk usage for no apparent reason!I have a full disk and need to find out which files are taking up too much space!........
  • View Disk Space Usage sorted by the size


    View Disk Space Usage sorted by the sizeUse: [code:1:8f675c5910]du -h | sort -n[/code:1:8f675c5910] The -h in du makes it show Kbytes or Mbytes instead of just bytes making it easier to read. The sort -n will show the files in order of smallest to largest *Note if you specify sort -nr instead then it will show the largest files first.........
  • Clustering Links


    Clustering LinksI thought this might be interesting for people with spare time. [b:6423c19973]Great clustering article from Linux Mag[/b:6423c19973] http://www.linux-mag.com/2003-11/clusters_01.html [b:6423c19973]General Linux cluster information[/b:6423c19973] http://www.gdargaud.net/Hack/ClusterNotes.html#HighA http://www.faqs.org/docs/Linux-HOWTO/Cluster-HOWTO.html#s3 http://www.yolinux.com/TUTORIALS/LinuxClustersAndFileSys........
  • SATA Power cable for 1U Server Solutions - Rosewill 8" SATA Power Cable Model RC-8"-PW-4P-2SA


    NewEgg is one of the few companies that stocks this great right angle 1U SATA power cable. I've purchased some no-name ones and they face the wrong way (towards the bottom of the chassis) which makes it worse/impossible than standard SATA connectors. The price is high but if you're building a 1U server and want SATA disks and don't have much space (eg. the 1U Supermicro cases) then these are simply a must and........
  • How to Track Down/Find Cause of Linux high disk iowait/wa


    top - 09:34:12 up 2 days, 20:57,  2 users,  load average: 1.83, 1.99, 2.03 Tasks:  59 total,   2 running,  57 sleeping,   0 stopped,   0 zombie Cpu(s):  0.3%us,  0.0%sy,  0.0%ni,  0.0%id, 99.7%wa,  0.0%hi,  0.0%si,  0.0%st That 99.7% wa is iowait, it means the server is waiting for a process to complete an IO operation or in plain English, there is a delay in........
  • Tyan S2735-8M Maximum Hard Drive Limit/Not Working/Doesn't work with 1TB 1000GB hard drives


    I never saved any of the logs, but basically no matter what OS (Linux) I used, I could not get my 1000GB hard drive to work (Seagate SATA).  The BIOS recognizes the drive and fdisk -l shows the hard drive as it should. The tricky thing is that different OS's will give you different results, but don't be fooled.  You can't use these larger drives for long.  I was getting all kinds of seek/IO errors and also messages that the port could not be read.........
  • Viewing and Connecting to an SMB Samba Share on Windows/Linux/Unix


    This will give you the basic info needed to browse and connect to Samba shares from the command line.  From the GUI of Gnome or KDE etc, it is pretty standard and straight forward.  However, I've found very little guides on how to do it from the command line and if you're like me, a nerd who prefers command line for its simplicity and for remote use, this is the way to go. First get a list of all the Samba/SMB shares on the target. smbclient -L hostname........
  • Rackable Systems and their Microslice Clustered 1U Servers


    I think there has been a lot of negative press towards Rackable Systems.  We will give their new solution credit that it is marketed very well, and comes prepackaged and ready to go. But let's cut through the hype of both sides, the people who love this concept and the people who hate it. What Rackable Systems have done is a first, to minimize space, power and costs into small servers.  This is great, and many companies have already built their own servers based........
  • Writing/Burning a data CD-R/DVD-R or DVD+RW in Unix/Linux


    There's a lot of outdated information and confusion for system administrator's out there. One annoying task for many an Administrator has been backing up data in Linux.  You don't need any GUI tools such as K3B or GnomeBaker.  Both are excellent tools but for veteran command line users working remotely, using the keyboard is a great and possibly automated way to save yourself pain and hassle. At a later date we'll cover how scripting can automatically backup certain........
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