Monday, May 25, 2009

VMs over ZFS rock

when configuring some complex task over a server, sometimes things go bad (corrupt files, wrong versions, bad data in DB ... etc) and sometimes it's really not easy to undo everything such that you're sure the machine is in a known-good-n-clean state. This is where VMs over ZFS rock!

while self.isPatient():
ssh vm poweroff;
zfs rollback vm@someTimeWhenThingsWhereGood
VBoxManage startvm vm
self.letsTryAgain()

Hyper cool! Snapshots and ease/reliability of backups/restores are about one of the most important things why I love virtulization.

3 comments:

SoreGums said...

What is your Host system?

I'm looking into setting up my 4 750GB sata disks into a zfs volume/group. They are currently in a mdadm raid10 setup and it is too slow for vm's (using virtualbox)

My host has 2xDual Core Xeons w/ 16GB RAM - only thing holding this box back is the i/o...

Cheers ;)

Ahmed Kamal said...

Hi SoreGums,

If you're sure disk IO is what's holding your server back, try adding more disks .. or simply use faster disks (SAS 15K .. or Fiber perhaps)

SoreGums said...

Those options involve spending cash. if i was going to spend cash I'd buy a hardware raid card...

I'm looking into going opensolaris :)