Tuesday, July 13, 2010

Is System Protection in a VM necessary?

I just happened to be working through the set-up of a new virtual environment and I was walking through my standard steps and it occurred to me that I always log in to my VMs and disable System Protection and delete any restore points.

I do this for a couple reasons.  One is to reduce the storage requirements of the VM, another is to just take that overhead out of the system.

I might be stilly for doing this, but it is one of the practices that I consider standard in my environments (as well as redundant and unnecessary). 

I mean, if I want to be able to restore my VM, don’t I use a snapshot (checkpoint)?  So, if I do that I have storage requirements, and then on top of that the OS in the VM is basically doing the same thing so it can roll itself back.

Actually, if i left it turned on it would give me the ability to pluck that patch back out when things go south and I forgot to take a snapshot.  It could be one of those stealth features that we don’t normally think about when managing VMs.  We always focus on what we can do at the hypervisor and forget what we can already do within the operating system of the VM.

Hmm..  Quite the puzzle.

I brought this up as it is something that just happened to pop into my head as being unusual, strange, not required, however strangely comforting.  You know, that whole ‘I do it my way’ type of thing for no right or wrong reason.

I would love to hear comments on this one.

1 comment:

Rob Daly said...

I do the same, Brian. The constant overhead that Windows system protection incurs is pretty substantial. It's also something that's either on or off. With VM level snapshotting (and dare I add storage level snapshotting) you can add and remove points in time as necessary with much better options for restoration/recovery. My perspective is, if you've chosen to virtualize a system, you should use the virtualization layer wherever possible to simplify tasks.