How To Upgrade to XenServer 6.2: My Story

This is my story on how I was able to upgrade our two virtualization stacks to XenServer 6.2. It is a tale of woe, so be prepared.

Where to begin …

We have two virtualization “stacks” consisting of four servers each. Two servers are for storage (Ubuntu 12.04 boxes using DRBD for replication) and two are XenServer hosts. At first we were hoping to use software RAID on the host boxes, but that did not work out.

So, we went ahead and purchased Adaptec RAID 6405 cards for the host boxes even though they were not on the HCL list for XenServer because we thought it would be easy enough to go ahead and create driver disks. While it is possible, it is still a pain.

Worse than that, when we attempted the upgrade to XenServer 6.2 from our 6.1 pools … the installation media would not see the prior installation even when using proper driver disks. We could do new installations, but we could not upgrade pools.

What!?

So … a new plan was hatched. Here are the steps:

  1. Purchase new LSI MegaRAIDSAS 9260-4i card as a replacement for the Adaptec RAID 6405 card currently in one of the host boxes.
  2. Install said card into host box and test installation of XenServer 6.1.
  3. After installation of XenServer 6.1, test upgrade to XenServer 6.2
  4. Reinstall XenServer 6.1 onto host.
  5. Run patches and add back into pool.
  6. Order three more RAID cards.
  7. Migrate VMs to the newly added pool member.
  8. Drop other host box with the Adaptec card still in it.
  9. Install new RAID card and install XenServer 6.1.
  10. Run patches and add back into pool.
  11. Upgrade all pool hosts and pool to XenServer 6.2.

Do that for each stack. It allows me to move each host box onto a RAID card supported by XenServer and then allows me to upgrade the entire pool to XenServer 6.2 using the mechanisms with XenCenter.

YAY!

I’ve learned a lot, again, through this entire process … maybe most importantly how vital it is to have a plan ready to go in your head before you start and to follow it as closely as possible. Luckily, this one worked.

I’ll have to wait and see if I am as lucky in the future.