/ - rtt - IT Resource

  • systemd management using systemctl and journalctl to check systemd logs


    systemd is like the service manager for your Centos and other modern Linux distributions (including Debian/Mint/Ubuntu) allows you to enable services, stop them, restart them, check their status and even reboot your system. The key commands or arguments you will use with systemctl are the following: Unit Commands:   list-units [PATTERN...]         List loaded units &nbs........
  • 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........
  • Centos 7 - How To Install NFS and Mount Remotely


    1.) First install nfs-utils [root@bcitcourse ~]# yum -y install nfs-utils Loaded plugins: fastestmirror base                                                         &n........
  • wodim / cdrecord error cannot burn DVD or BDR .iso Errno: 5 (Input/output error), write_g1 scsi sendcmd: no error


     dvd+rw-mediainfo /dev/sr0 INQUIRY:                [ASUS    ][BW-16D1HT       ][3.00] GET [CURRENT] CONFIGURATION:  Mounted Media:         11h, DVD-R Sequential  Media ID:              RITEKF1  &n........
  • NFS Share Won't Mount Solution - mount: wrong fs type, bad option, bad superblock on 10.10.2.20:/tmp/nfsmount


    nfs mount failed: mount 10.10.2.20:/tmp/nfsmount /mnt/nfs/ mount: wrong fs type, bad option, bad superblock on 10.10.2.20:/tmp/nfsmount,        missing codepage or helper program, or other error        (for several filesystems (e.g. nfs, cifs) you might        need a /sbin/mount.<type> helper program)       ........
  • 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........
  • How To Install Windows Server 7 8 10 12 2008 2012 2014 2016 Servers Desktops using Linux tftp, dhcpd and samba


    It has been a big pain for a long-time to install Windows from a Linux environment.  I used to run a windows install server and it never worked right for some reason (the install would fail on most servers). Before getting start be sure to setup your samba share so once you boot into WinPE you can mount the install for whatever Windows you want /etc/samba/smb.conf [smbwinstall] path = /tftpboot/images/winstall guest ok = yes........
  • OpenVZ Solutions vzquota : (error) Can't open quota file for id 123123, maybe you need to reinitialize quota: No such file or directory


    Error: Unable to apply new quota values: quota not running Container start failed (try to check kernel messages, e.g. "dmesg | tail") Killing container ... Container was stopped Error: Unable to apply new quota values: quota not running Can't umount /vz/private/123123: Invalid argument [root@rtt 123123]# vzquota on 123123 vzquota : (error) Can't open quota file for id 123123, maybe you need to reinit........
  • Install Windows From a Linux TFTP Server instead of using WDS Solution


    yum -y install samba vi /etc/samba/smb.conf https://www.kernel.org/pub/linux/utils/boot/syslinux/syslinux-6.03.zip mkdir syslinux;cd syslinux;unzip syslinux-6.03.zip mkdir -p /tftpboot/libs/ cp bios/com32/modules/linux.c32 /tftpboot/libs/ cp bios/com32/libutil/libutil.c32 /tftpboot/libs/ cp bios/com32/lib/libcom32.c32 /tftpboot/libs/ #add lib path echo "PATH libs" >> /tftpboot/pxeli........
  • cannot mount kvm ntfs image


    guestmount -a kvmuserscra.img -m /dev/sda1 mount libguestfs: error: mount_options: /dev/sda1 on / (options: ''): mount: unknown filesystem type 'ntfs' guestmount: '/dev/sda1' could not be mounted. guestmount: Did you mean to mount one of these filesystems? guestmount:     /dev/sda1 (ntfs) guestmount:     /dev/sda2 (ntfs) yum -y install ntfs-3g still........
  • mdadm how to mount inactive array


    myguy@devbox:~$ sudo mdadm -As myguy@devbox:~$ cat /proc/mdstat |grep sdf md125 : inactive sdf3[2](S) sudo mdadm --manage /dev/md125 --run mdadm: started /dev/md125  ........
  • How to find and mount mdadm arrays automatically


    A great way if you have a bunch of drives and mdadm connected and are looking for backups/archives and don't know what is where!    for md in `cat /proc/mdstat|grep md[0-99]|awk '{print $1}'`; do mkdir /mnt/$md; mount /dev/$md /mnt/$md; done........
  • Linux Unable to mount cifs/smb share in /etc/fstab


    sudo mount -a Unable to find suitable address. [35758.706993] CIFS VFS: Error connecting to socket. Aborting operation. [35758.707247] CIFS VFS: cifs_mount failed w/return code = -111 [35795.476160] CIFS VFS: Error connecting to socket. Aborting operation. [35795.476346] CIFS VFS: cifs_mount failed w/return code = -111 When the above happens "Unable eto find suitable address" it usually means the smb nam........
  • ecryptfs how to mount or recover from a backup


    The easiest way to recover or mount an off-line ecryptfs directory is the built-in command from ecryptfs sudo ecryptfs-recover-private It will find your wrapped passphrase and ask for your password and mount it in tmp. Much easier especially when your current active OS is using ecryptfs too. This a fantastic tool when going through old backups.........
  • OpenVZ error : Container start failed (try to check kernel messages, e.g. "dmesg | tail") Locked by: pid 166638, cmdline vzctl start 888171


    This container won't start after exhausting its memory.  There are no relevant or helpful messages in dmesg or vzctl.log as well.  Standard troubleshooting such as disabling PPP etc has not helped.   2017-07-06T23:33:29-0400 vzctl : CT 888171 : Locked by: pid 166029, cmdline vzctl start 888171 2017-07-06T23:33:29-0400 vzctl : CT 888171 : Container already locked 2017-07-06T23:33:29-0400 vzctl : CT 888171 : Container was stopped 2017-07........
  • 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........
  • How to change reserved blocks in Linux partition


    user@box:~$ sudo tune2fs -l /dev/md99 [sudo] password for user: tune2fs 1.42.9 (4-Feb-2014) Filesystem volume name:   <nuser> Last mounted on:          /mnt/md50 Filesystem UUID:          976a8655-2619-4587-878c-dab07f7b7652 Filesystem magic number:  0xEF53 Filesystem revision #:    1 (dynamic) Fi........
  • 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........
  • Linux Mint Install Netboot PXE Guide Howto


    *Update so this doesn't work it must be something to do with the path of nfs or something else but the installer fails with "Installer crashed" at the end whereas with the CD/USB it works. This assumes you've already installed and configured a separate PXE/DHCP server somewhere else and your /tftpboot directory is setup. This is for Linux Mint 18.1 but generally applies to most versions although you may have tro change things like "casper"........
  • ecryptfs errors


    ecryptfs-mount-private Enter your login passphrase: Inserted auth tok with sig [ee16d84] "into the user session keyring mount: No such file or directory" [  156.118113] ecryptfs_mount: kern_path() failed [  156.118431] Reading sb failed; rc = [-2] [  164.233055] traps: mate-notificati[3472] trap int3 ip:7f43d7002c13 sp:7fff162c6600 error:0 [  166.017061] ecryptfs_mount: kern_path() failed........
  • 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 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........
  • Unable to mount location Failed to retrieve share list from server: No such file or directory solution


    Cannot even "Browse Network" when clicking on "Windows Network" Unable to mount location Failed to retrieve share list from server: No such file or directory logs: [2017/02/14 00:16:44.271314,  0] ../source3/nmbd/nmbd.c:58(terminate)   Got SIGTERM: going down... [2017/02/13 17:35:41.797944,  0] ../lib/util/become_daemon.c:124(daemon_ready) &........
  • mdadm kernel panic if trying to change --layout on a RAID10


    It is already known this is not possible   mdadm --create /dev/md3 --level 10 --layout=f2 --raid-devices=2 /dev/sdc1 /dev/sdd1 mdadm: /dev/sdc1 appears to be part of a raid array:        level=raid10 devices=2 ctime=Sat Dec 24 18:44:29 2016 mdadm: /dev/sdd1 appears to be part of a raid array:        level=raid10 devices=2 ctime=Sat Dec 24 18:44:29 2016 Continue creating ar........
  • OpenVZ Solution CPT ERR: c02fa000,73 :CPT: lock fd is closed incorrectly: 1 and vps-net_add ERROR: Unable to add route ip route add 192.168.5.2 dev venet0


    The only solution after trying many suggestions was to simply restart the "vz" service (definitely not preferable). Even doing an ifdown and ifup for venet0 did not help. ifup venet0 Bringing up interface venet0: Configuring interface venet0: net.ipv4.conf.venet0.send_redirects = 0 RTNETLINK answers: Network is down Some errors from log:   CPT ERR: d2dc60........
  • mdadm change wrong device name md127 fix and solution in Linux


    md127 issue, it should be /dev/md3 per mdadm.conf Any time something is mounted as md127 it almost always means there is no entry for this mdadm array in the mdadm.conf in initramfs (which is separate from your actual /etc/mdadm.conf). cat /etc/mdadm.conf ARRAY /dev/md3 metadata=1.2 UUID=b6722845:381cc94e:7a2c5b5f:8e3b7c4f The reason for this is something strange, most Linux OS's bizarrely always keep their own copy of /etc/mdadm.con........
  • OpenVZ Migration Hostnode Containers from Centos 5 to Centos 6


    migrating from an old OpenVZ (Centos 5) to new OpenVZ (Centos 6) Also if migrating from 32-bit HN to 64-bit your RAM will probably be much bigger than it should be! 16x bigger eg. 32bit HN:              total       used       free     shared    buffers     cached Mem:&nb........
  • Openvz error solutions Container already locked (error) can't lock quota file, some quota operations are performing for id 1200


    rm /vz/lock/1200.lck rm: remove regular file `/vz/lock/1200.lck'? y vzctl start 1200 Container already locked vzctl start 1200 Starting container ... vzquota : (error) can't lock quota file, some quota operations are performing for id 1200 vzquota on failed [7] vzquota off 1200 vzctl start 1200 vzquota on 1200 root@rttbox ~]# vzquota off 1200 vzquota : (........
  • 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........
  • 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........
  • Mount a SMB Samba share in fstab Linux Debian/Ubuntu/Centos


    Add the following to fstab where 192.168.1.125/Media is the samba share and where /home/homeuser/Downloads is where you want to mount. Change user and pass to what is needed (if no pass is required it still works fine with the below). //192.168.1.125/Media /home/homeuser/Downloads cifs        user=guest,pass=bla 0 0 mount: wrong fs type, bad option, bad superblock on //192.168.1.125/Media, &nbs........
  • 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........
  • 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........
  • mount -o bind permanent in /etc/fstab howto


    mount -o bind /somedir /anotherdir In /etc/fstab /somedir /anotherdir none bind 0 0........
  • 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........
  • Dell CS24-NV7 lspci dmidecode info


    0000:00:00.0 RAM memory: NVIDIA Corporation MCP55 Memory Controller (rev a2) 0000:00:01.0 ISA bridge: NVIDIA Corporation MCP55 LPC Bridge (rev a3) 0000:00:01.1 SMBus: NVIDIA Corporation MCP55 SMBus (rev a3) 0000:00:02.0 USB controller: NVIDIA Corporation MCP55 USB Controller (rev a1) 0000:00:02.1 USB controller: NVIDIA Corporation MCP55 USB Controller (rev a2) 0000:00:05.0 IDE interface: NVIDIA Corporation MCP55 SATA Controller (rev a3) 0000:00:05.1 I........
  • 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          ........
  • Cannot mount iPhone or iPad in Linux


    Unable to mount iPad 4 Unhandled Lockdown error (-4) This is because you need the libimobiledevice-utils package installed and a newer version of it. My older Ubuntu 10.10 uses a version that does not have "idevicepair" which seems to work perfectly and automatically with newer versions of the library. Basically if you install the above library it should be plug and play and if your imobiledevice-utils doesn't have 'idevice........
  • drbd won't create device if previous partition is on it Command 'drbdmeta 0 v08 /dev/md160 internal create-md' terminated with exit code 40


    This is what fixed it: [root@box13 ~]# dd if=/dev/zero of=/dev/md160 bs=512 count=500 Basically you need to wipe out more than just the 512 byte partition table so 512 bytes * 500 is more than enough to make DRBD happy and think the partition is now empty. The reason this happens is because it gets confused when there is a previous partition with data on the device you are using.   root@box13 ~]# d........
  • 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........
  • Linux Howto Mount CD/DVD drive for sharing for other users


    sudo mount -o user /dev/sr0 cd You need the "user" option otherwise non-root or non-owners cannot view the CD and this would make it so no anonymous access to the CD/DVD mount would work.  Note that most distributions including Ubuntu DO NOT work unless you manually mount and share as shown above (I couldn't find any other way in Ubuntu).........
  • Migrate Linux Mint OS from one drive to another


    mount -o bind /proc /sda2/proc mount -o bind /dev/ /sda2/dev mount -o bind /sys /sda2/sys chroot /sda2 mint / # mount -o bind /proc /sda2/proc mint / # mount -o bind /dev/ /sda2/dev mint / # mount -o bind /sys /sda2/sys mint / # chroot /sda2 mint / # cd ~ mint ~ # ls Desktop mint ~ # cd / mint / # ls bin   Desktop  dev-temp  home      &nb........
  • vzquota : (error) Quota on syscall for id 42131: No such file or directory vzquota on failed [3]


    Starting container... vzquota : (error) Quota on syscall for id 42131: No such file or directory vzquota on failed [3] Solution cd /var/vzquota mv quota.42131 quota.42131-disable  vzctl start 42131 Starting container... Initializing quota ... Container is mounted Adding IP address(es): Setting CPU units: 1000 Container start in progress...  ........
  • 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).........
  • Wordpress Custom Menu Limit Fix/Solution


    This is usually solved by two variables alone: max_input_vars=5000 memory_limit=256M Now you should be able to have unlimited amounts of custom menus in Wordpress.........
  • 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........
  • 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      ........
  • Openvz "Container is currently mounted (umount first)" solution


    Container is currently mounted (umount first) The container is stuck in the "mounted" state, you must manually start it to get it out of that state (there is no umount option as implied by OpenVZ vzctl).........
  • OpenVZ Container Can't Restart, stuck in mounted state


    When trying to reboot this Centos 5 container, it gets stuck as "mounted" and requires a manual start command, here is what dmesg shows:   [424458.173252] VE10000: no allowed mount options found for device 0:21 [424458.177970] proc: unrecognized mount option "relatime" or missing value [424460.297663] CT: 10000: stopped [426663.466433] CT: 10000: started........
  • LVM How-To Activate and Access Volumes/Data


    vgchange -ay   3 logical volume(s) in volume group "vg_12" now active lvscan   inactive          '/dev/vg_12/lv_root' [144.04 GB] inherit   inactive          '/dev/vg_12/lv_home' [1.00 GB] inherit   inactive          '/dev/vg_12/lv_swap' [7.85 GB] inherit........
  • Linux/Debian shutdown/reboot without going through init force


    -bash-3.1# shutdown -rn now Connection to localhost closed by remote host. Connection to localhost closed. Sometimes I work with embedded systems/custom kernels without any of the fancy init scripts and other common Linux basics that most would expect.  This means that often the "reboot" command (which uses an init script) will never work, not only that but it will hang the server and a manual power cycle or reboo........
  • 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........
  • lvm resize and use the remaining extra space


    df -h Filesystem            Size  Used Avail Use% Mounted on /dev/mapper/vg_12-lv_root                        50G  1.2G   46G   3% / tmpfs                 7.8G     0&nb........
  • 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........
  • 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........
  • setquota: Mountpoint (or device) / not found. setquota: Not all specified mountpoints are using quota. with openvz solution


    Directadmin Error when changing user settings/saving Details Error with system Quotas setquota: Mountpoint (or device) / not found. setquota: Not all specified mountpoints are using quota. Debug Guide   You have to disable and enable the quota's using vzquota on and off. After that it will work.........
  • 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........
  • 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   ........
  • mdadm/Debian problem


    This is one in a series of weird things which I thought was motherboard related (I RMA'd the motherboard), the RAM tests fine with memtest86 and I used badblocks on both RAID 1 members with no errors and smartctl is happy with them. Basically the array crashes the kernel a lot and has issues when writing.   [112322.723465] md0: rw=0, want=14958668696, limit=1887460480 [112322.731077] attempt to access beyond end of device [112322.731087] md........
  • Linux Out of Memory OOM Object Killer Solution "Out of memory: kill process 1955 (sshd) score 81 or a child"


    I had a system running a 128MB live CD image with 2.8 gigs of available RAM and the OOM kernel killer went crazy when using dd for more than 8 minutes and kept killing everything.  I've read that this is due to a low-memory issue and paging in the kernel and 32-bit systems with lots of RAM. I even enabled swapspace on my LiveCD and the issue happened 25 minutes into dd rather than 8 minutes, so what gives? Also no swap space was ever used! cat /proc/s........
  • 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........
  • Linux High IOWAIT updatedb can't be killed and crash with mdadm


    high IO wait   424 root      39  19  1900  848  552 D  0.0  0.0   0:00.91 updatedb root       424  0.0  0.0   1900   848 ?        DN   Mar11   0:00 /usr/bin/updatedb -f sysfs?rootfs?bdev?proc?cpuset?binfmt_misc?debugfs?sockfs?usbfs?pipefs?anon_inodefs?futexfs?tmpfs?inotifyfs?eventp........
  • 95th Percentile Billing vs Usage Billing, what's better?


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  • sshfs cannot unmount error: device is busy. (In some cases useful info about processes that use the device is found by lsof(8) or fuser(1))


    umount: /home/diret/mount: device is busy.         (In some cases useful info about processes that use          the device is found by lsof(8) or fuser(1)) I tried everything (fusermount -u) to unmount it but the only thing that worked was actually doing this: ps aux|grep sshfs Then I identified the sshfs connection and did: kill -kill pid........
  • 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........
  • 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........
  • 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........
  • How to chroot properly into your OS/distro


    From a LiveCD or if you're doing something like converting your non-RAID install to mdadm here's how you would chroot properly (you have to mount your proc, sys and dev on the running system/LiveCD to your chroot environment if you want things to work right, especially if you need to run update-initramfs due to a driver change etc..) *replace "path" with your mount/chroot path mount -o bind /proc /mnt/path/proc mount -o bind /dev/ mnt/pa........
  • Error: DBus error org.freedesktop.DBus.Error.ServiceUnknown: The name :1.1127 was not provided by any .service files Please select another viewer and try again.


    This is an SFTP mount that does not work or prompt for password. Error: DBus error org.freedesktop.DBus.Error.ServiceUnknown: The name :1.1127 was not provided by any .service files Please select another viewer and try again. It seems to me that the connection often times out after being opened and the application doesn't know how to handle the disconnection and doesn't realize it needs to kill the instance and restart the connection.........
  • Openvz Live Migration Error - Error: undump failed: Invalid argument Restoring failed: Error: iptables-restore exited with 2 Error: Most probably some iptables modules are not loaded Error: rst_restore_net: -22


    Adding IP address(es): 192.168.5.8 192.168.5.9 Setting CPU units: 1000 Error: undump failed: Invalid argument Restoring failed: Error: iptables-restore exited with 2 Error: Most probably some iptables modules are not loaded Error: rst_restore_net: -22 Container start failed Stopping container ... Container was stopped Container is unmounted Error:  Failed to undump VE Resuming... vzquota : (erro........
  • Ubuntu 10.04 Linux is still not ready for the Desktop world


    I am a huge fan of Linux and the idea of OpenSource but I've said it many times, there are still hurdles in today in 2010 for Linux as a Desktop.  Linux is still intended for servers at its very core.  This can be changed succesfully though, as Apple has shown us with Mac OS X based on FreeBSD. Half of the issue is lack of driver support and the other half is the Linux Kernel and Window Manages, KDE and GNome still both don't cut it (but they're getting closer). I'll........
  • Shutdown/Power/Halt In Debian/Ubuntu/Centos Guide Systems Doesn't Work


    Different distributions such as Debian and Centos behave differently when trying to shutdown your system. shutdown -H now on Debian does not do what you'd expect.  The system won't power down, it will halt and do everything but power down. shutdown -PH now will do the job though (actually power the system off).  This is important to test especially if you are not near the system.  If you just use -P it forcefully shuts off which is not........
  • FUSE/Curlftpfs mount ftp account as drive partition in Linux


    This is a great way to use your ftp server space, for example on your web hosting account (although I believe many hosts don't allow storage like this), but if you have a VPS/Dedicated Server etc.., this would be perfect.  Imagine how easy it is to work with an ftp account that you can just mount as a normal partition or directory in Linux, it would be great for backups etc..   Name curlftpfs - mount a ftp host as a local directory Synopsis........
  • LUKS/cryptsetup Tutorial for Linux Hard Drive Partition Encryption


    This is based on Debian Linux but should apply equally to any *nix distro. Install LUKS/crypt-setup apt-get install cryptsetup Setup your LUKS Partition Of course change /dev/md2 with whatever partition you intend to use LUKS on. cryptsetup --verbose --verify-passphrase luksFormat /dev/md2 You'll be asked to verify your decryption password twice *DO NOT FORGET THIS PASSWORD AS IT IS NOT RECOVERABLE!........
  • 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 can you downgrade the superblock?


    Why would you want to downgrade the superblock?  Old mdadm verisons like mdadm 2.5.6 only use the 0.90 superblock/metadata and new versions use 1,1.0,1.1 and 1.2 superblocks by default. There are some annoying caveats with this, first of all the new superblocks (later than 0.90) CANNOT be read by GRUB, so you won't even be able to install GRUB.  Even worse, old versions of mdadm CANNOT automatically detect arrays even if they were created with a new version of mdadm with th........
  • mdadm force/fix proper md127 name


    I have an md0 arary that my Centos install refers to.  I feel this is half the reason why it won't boot anymore. I saw the initrd for Centos was assembling it as md127 even though it was known as md0. The reason for this is because I used mdadm --assemble --scan to detect the array on a LiveCD.  I had no idea this name would stick (but now I realize the name is permanently stored in the metadata once you mount md127 or whatever random name assemble gives it).  W........
  • Great way to backup/clone/dd your Linux partitions


    Partclone is a great tool that is basically like dd only it does not waste space, it doesn't take the whole partition, yet it does the same thing as dd, only with huge space/cost savings. Clonezilla uses partclone and is more of an integrated/easy to use suite I guess you could say.  I've personally only used partclone but I wish there was an easy way to mount partclone images. I believe with Clonezilla you can do that, so I will probably give it a shot next time.........
  • Debian 5.04 RAID 1 mdadm boot problem GRUB error


    I successfully created a single RAID 1 partition which includes /boot inside it and my root directory through the Debian installer.  It said GRUB installed successfully but when I try booting the OS it seems GRUB can't read anything. When trying to boot from GRUB GRUB Loading stage 1.5. GRUB loading, please wait... Error 2 I get "Error 2" when trying to boot Debian.  I also notice from a LiveCD that........
  • Centos 5.5 RAID 1 boot issue


    I installed 5.5 with a 300GB RAID 1 partition (boot is also on this partition).  It booted up fine the first few times until after I used a Live CD and accessed the array, and it became named /dev/md127 for some reason. Now whenI boot into CentOS I get a kernel panic and different errors, once I got "invalid superblock", even though the array is fine (it didn't happen again, probably because I was sure to dismount and stop the mdadm array properly). Here's what........
  • 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........
  • 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........
  • 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........
  • OpenVZ backup container to a single file while it's running using "vzdump"


    Proxmox has made this free utility to backup running OpenVZ containers.  It's a great program which is actually just a PERL script but gets the job done.  This program is not 100% required because all it really does is cp -a from your container's path as far as I know but it is still good to have uniformity to how you backup your containers. For RPM distros such as Centos/RHEL/Fedora etc.. download and install this: wget http://www.proxmox.com/cms_proxm........
  • 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........
  • 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........
  • PHP cannot access /usr/bin/openssl


    PHP cannot access /usr/bin/opensslI have verified the username that runs the process is able to access /usr/bin/openssl and it does exist but the PHP script is saying it doesn't exist: [code:1:1fd0f3abbe] if (!file_exists($OPENSSL)) { //echo "ERROR: OPENSSL $OPENSSL not foundn"; }[/code:1:1fd0f3abbe] I don't get itI can clearly see the contents of /usr/bin by using the PHP system fu........
  • 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........
  • Mounting NTFS in Unix


    Mounting NTFS in UnixJust a quick tutorial to mount your NTFS volumes in Unix (FreeBSD/Linux) [quote:4a9de7bf80]mount -t ntfs -o umask=0 /dev/your_partition /mnt/your_mount_point[/quote:4a9de7bf80] [b:4a9de7bf80]-o umask=0[/b:4a9de7bf80] is to ensure all users can access the mounted partition (otherwise don't use it and only root can access the mounted partition) [b:4a9de7bf80]-t ntfs[/b:4a9de7bf80] is simple because it just lets mount kno........
  • sed is great for pattern matching or retrieving lines


    sed is great for pattern matching or retrieving linesHere is a cool example Say you type df: The output would be something like: [quote:3bb8d51437]Filesystem 1k-blocks Used Available Use% Mounted on /dev/hda2 1712432 1206664 418780 75% / /dev/hda1 31201 10505 19085 36% /boot none 30932 0 30932 0% /dev/shm [/quote:3bb8d51........
  • 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........
  • GRUB "Error 2: Bad file or directory type" 0.97 won


    You can see the problem below, GRUB recognizes my hard drive and sees the partitions but cannot access them.  This is from the GRUB boot disc I'm using. What happened is that I had some power issues causing this system's power to be interrupted several times and basically an on/off on/off situation. The system won't boot, I just get a flashing cursor and no message or error from GRUB.  Obviously the problem is that my MBR seems corrupt or some other issue. My........
  • Clustered/Distributed Network Filesystems, Which Ones live up to the hype?


    I've tried to find a good sensible solution to cluster with and each technology has it's pros and cons and there is no perfect solution and I've found a lot of "exaggerations" in the applications, benefits and performance of these different filesystems. DRBD I first started off with DRBD and I have to say it does live up to the hype, is quite reliable (although it can be annoying to match up the kernel module and user applications since they must match and whe........
  • OpenVZ/Virtuozzo Enable Fuse in Container


    To enable Fuse to work inside a OpenVZ container it's very simple (although some people say it can't be done). Remember that on your HN (HostNode) for OpenVZ, Fuse must be installed and the module must be loaded for this to work.  In addition remember that you need the Fuse package installed inside the container of course. vzctl set 2000 --devices c:10:229:rw --save vzctl exec 2000 mknod /dev/fuse c 10 229 The part that most people forget........
  • Using a Mac OSX DMG Image in Windows and Converting to Standard ISO Format use dmg2iso


    The dmg format is silly and annoying to work with, why couldn't Apple stick with the .iso standard?  Anyway, there's an excellent Linux and Windows based tool to convert it back to a normal .iso Image called dmg2iso I'll only cover the Linux version although the Windows pre-built binary works the same way. Download dmg2iso here for free (from the author's website) It's just silly and doesn't make sense that Ubuntu doe........
  • OCFS2 crash


    When trying to even cd or ls the mounted OCFS2 partition it crashes.  I think this is a combination of VMWare Server's problem and the way I mounted and symlinked to it. More than anything this shows the problem and lack of forsight with VMWare, but also that OCFS2 is easily crashed if you do strange things. Output of /var/log/messages for OCFS2   Apr 10 15:57:45 localhost kernel: [84331.691258] Modules linked in: vmnet vmci vmmon ocfs2_stac........
  • Configuring OCFS2 Clustered File System on Debian Based Linux including Ubuntu and Kubuntu


    There's a lot of information and guides on OCFS2 for RHEL and Centos Linux but the package setup and configuration is slightly different and this has thrown some people off. Installing OC2FS You should install the following packages to get started: apt-get install ocfs2-tools ocfs2console Configure OC2FS In RHEL/Centos the main configuration file is located in /etc/sysconfig/o2cb However in Debian based Linux it is located........
  • 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........
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