Had a great webinar yesterday with about 200 attendees. The title was “The Six Fairytales of VMware and Hyper-V Backup” (the actual webinar is here.) The best part from my perspective were the questions. I thought I’d share some of the questions – and answer those questions now in writing – in a few blog posts.
One person asked about how the things discussed in the webinar applied to XenServer. What I talked about was the fact that XenServer traditionally didn’t have an HOS level backup and that in the past “rsync” was recommended for protection at the HOS level. XenServer of course can always be backed up at the GOS level – and now has a disk snapshot capability. Thus XenServer can be snapped at the HOS level now manually with XenCenter. Scripted snaps are supported via the XenServer CLI (remotely) or via the XenServer API call.
Another person asked about whether they should be concerned using Hyper-V and backing up the VHD file to a USB 3.0 drive each night. I told them that my major concern would be automating the process – because there are a lot of studies that show that when you don’t automate data protection, you end up forgetting it at exactly the time you need it most. Beyond that, the key to making this successful is to quiesce in some fashion your virtual machines so that your VHD is consistent. The quiescing is the key to all virtual machine (and for that matter, physical machine) backups – basically, you have to make sure what’s on the disk when you back it up can be recovered from in a consistent state. If you don’t quiesce, then what happens is that your copy of the VHD (or any other data on a virtual or physical disk) will appear corrupted since some of your data was in memory and some was on the disk when you copied that virtual or physical disk.
Over the weekend and next week I’ll do a few more posts on the great questions asked during this webinar. Thanks to everyone who participated!