Tag: 6.2

Citrix XenServer Error: SR_BACKEND_FAILURE_65

I’ve been having issues attaching a VDI to a VM from a NetApp snapshot.  Basically a storage level snapshot that happen while the server was live.  I keep getting the error “The attempt to load the VDI failed” via XenCenter when I try and boot the VM.  I would then look at the log file: /var/log/xensource.log.  I would see that the VM was tossing out the error “SR_BACKEND_FAILURE_65” when it tried to boot.

I have been unable to get the VDI to load on any server.  I even contacted Citrix looking for help and they were unable to get the VDI to load as well.  I’ve seen several others on the internet run into this issue without a resolution.   If someone knows of a trick to get these VDIs to load, please leave a comment!

Hope this helps!

Citrix XenServer Error: The SR failed to complete the operation

Yesterday we started to run out of space on one of our storage repositories.  When we tried to move any VDI on that SR via XenCenter, we got the error “The SR failed to complete the operation”.  Which is a pretty generic error, par for xenserver errors.  I even got the same error when trying to do a ‘Rescan’.

I continued to troubleshoot, looking through logs and command outputs.  I finally found something to look into.

Ran the command (use the UUID of a SR you’re having issues with):
xe sr-param-list uuid=eb943814-a329-5f84-bd42-af1858d56632

Noticed this parameter:
other-config (MRW): dirty: ; auto-scan: false

I looked into this “dirty” param…  It means xenserver isn’t happy with the file names on the SR.   I listed the files on my SR and saw that someone created a copy of a VDI called: Copy of f897ebcf-9365-471b-8a30-e81f564c2536.vhd.

I fixed it by:

  • ls /run/sr-mount/eb943814-a329-5f84-bd42-af1858d56632
  • Found file that shouldn’t be here called Copy of f897ebcf-9365-471b-8a30-e81f564c2536.vhd
  • Removed the file Copy of f897ebcf-9365-471b-8a30-e81f564c2536.vhd
  •  Rescanning the SR
  •  I was then able to move the VDI from one SR to another with out error in xencenter.

Hope this helps with your day:

Citrix XenServer 6.5 Performance Comparison

Noticed this on the Citrix blog today. A nice little performance comparison between ESXi 5.5 and XenServer 6.5. Citrix claims to show a 11-16% performance advantage over VMware.  I’m holding off on upgrading to 6.5 till summer, but can’t wait to run some of my own benchmarks against XenServer 6.2.

Citrix XenServer Upgrade From 6.1 to 6.2

This weekend I’ve updated from 6.1 to 6.2. Here are the steps I took to do the upgrade.

  1. Make sure you have upgraded your licenses to 6.2 (May require login).  They have changed to a per socket structure, for us we have two sockets per server, and was able to upgrade without paying extra.  The upgrade will warning you if you don’t have the 6.2 license, but you can continue on… just make sure you’ve got the new 6.2 license is applied to your license server.
  2. Download the XenServer-6.2.0-install-cd.iso file (May require login)
  3. I uploaded the file to a physical linux web server not part of my Xen pool
  4. Create a directory called ‘xen’ in the root of your web site
  5. Mount the ISO as a loop device: 
    sudo mount -o loop XenServer-6.2.0-install-cd.iso xen/
  6. Update XenCenter.msi to the latest version. After updating XenCenter, “About XenCenter” shows my version as “6.2 (build 1377)”
  7. Backup your XenServer Pool, ssh into your pool master and run this command.  Copy into your backups on a file server 
    xe pool-dump-database file-name=xenpool.backup.20140510
  8. Disable HA
  9. Shutdown any unneeded VMs, this will decrease the time it takes to preform the upgrade
  10. To preform the upgrade, in XenCenter goto Tools -> Rolling Pool Upgrade
  11. Select your pool
  12. Select ‘Automatic Mode’
  13. Obey the rules of the pre-check
  14. Run the upgrade.  I had a few issues and had to restart the rolling upgrade, which didn’t seem like an issue.  My issues were mostly VMs loosing their VDIs, which can be fixed via this article.