XenServer and Exchange VM

[wesleyw]

Having real problems moving my existing Exchange VM to another pool server and SAN. I've tried a direct export from XenCenter, Snapshot and Export, Alike DR Replicate, Alike DR Enchanced Backup and Restore etc.. but they are still failing. Does anyone have another suggestion I can use to do this (preferably without paying out anymore money)?

Wes

[mmoseley]

How weird, I've moved my Exchange Server on XenServer before, I know this doesnt help you lol but its definetly possible...thats within Xen directly....:/

[dhicks]

Does anyone have another suggestion I can use to do this (preferably without paying out anymore money)?

I don't know what the exact problem is, but a couple of points gained by recent bitter experience might come in handy:

How do the SANs allocate storage internally, and how are VM disk images mounted to your VMs? Given an iSCISI volume, XenServer creates a Storage Repository (SR) on it, which consists of a Linux LVM volume with a fixed-size metadata volume at the start. If you are using a Linux-based OS on the SAN (e.g. Debian) to export an LVM volume for use as an iSCSI LUN, confusion can arise on reboots as the SAN's OS will see an LVM volume with further LVM volumes inside and, by default, mount the lot locally, resulting in a read-only iSCISI LUN.

The metadata logical volume contains assorted data about each XenServer VM disk image, including its name, in XML format. Note that that's not "in a file on the metadata logical volume", it's written directly to the logical volume itself. Unfortunatly, someone forgot to escape the ampersand character before storing volume names, so if you include an "&" in a disk volume name XenServer becomes unable to parse the metadata volume and your central storage repository falls over. The way to fix this (apart from simply avoiding the "&" character anywhere in XenServer) is to remove the metadata volume, while XenServer is still running, and it will then be re-created when you rescan the volume.

XenServer SRs are simply LVM volumes, so you should be able to simply clone one disk image to another using DD or whatever other tool you fancy. You can log in to each XenServer host via SSH to use standard Linux command-line tools to deal with LVM volumes and so forth. I'd guess your best bet might be to clone your Exchange VM with DD to an identically-sized volume on your second SAN - if you have both SANs mounted on the same XenServer host, it should simply be a case of doing "dd if=... of=..." and leaving it to run.

[sukh]

why do you need to move? have you got another exch server you can move services over to?

[wesleyw]

@mmoseley: Yeah I've moved them before to just messing about with this one sadly
@sukh: Sadly a single Exchange site here, though based on Exchange 2010 EES that may change

[sukh]

Haven't seen the new updates but I know there have been some changes around virtualisation and moves, not sure if Exchange is supported in this scenario?