XenServer 6.2 -> 6.5

In preparation for the upgrade from XS6.2 to 6.5 at my day job, I’m removing the XenTools drivers/software from our VMs (apparently old versions of the tools can cause booting issues for Windows VMs at the very least).

Something I hadn’t realised – removing the XenTools suite will cause Windows to lose its network drivers and revert to network defaults (which I guess should have been obvious? Not sure.).

Network defaults being DHCP for IP address, meaning our VM server just got assigned a client IP and for all intents and purposes couldn’t be found by the client software on our actual client machines.

Not a big deal or a hard fix in the end (VM reboot -> manually assign IPs again), but a reminder to self that this whole upgrade process will be a painful in both expected and unexpected ways.


The actual upgrade went well. Larger orgs usually have a physical server pool and upgrade using something called “rolling pool upgrades”.

We don’t have this, we’re poor. As a result, we have one main server with heaps of RAM and a second, backup server with enough resources to run essential VMs.

In the event of disaster, we can recover a VM image to the backup and pick up where we left off until a replacement main server is arranged.

So no rolling upgrades for us – instead I just prepped the VM images (as above) and then upgraded the backup server first (which, in case you’re wondering involves rebooting the physical server and running the installer from the ISO – either a USB or CD, of all things, and just selecting “upgrade” rather than “install and destroy all my stuff forever”) to verify everything would be running okay.

Once we were sure the backup could run our images on 6.5, we then processed the main server.

The whole process was significantly faster than the preparation, and there were no issues. Very impressed.

6.5 doesn’t do a heck of a lot for us overtly (although I’m quietly upgrading our Ubuntu VMs to 14.04), but there are a slew of improvements and I’m not sure whether it’s a coincidence or not, but our SVN/Dev/Local DB server is no longer having weird reboot issues.

Hooray for progress!