Partitions on virtual servers

[Bruce123]

Afternoon all,

 

Just query about how other people handle partitions when commissioning their new virtual servers.

 

On most of our physical servers we have:

 

C: RAID 1 (OS and applications)

D: RAID 5 (Data)

 

The logical drives map closely to the physical storage configuration and users get the performance benefit of having OS I/O and Data I/O on seperate arrays.

 

However, the performance argument for retaining this convention on virtual servers is a weak (as they are stored on the same storage unit and won't see much, if any, peformance benefit).

 

We have kept the convetion of C: and D: for our new virtual servers, mainly as a logical partition of OS from Data. But I do suspect that there are other specific technical reasons for wanting to maintain the seperation, but I can't actually think what they would be. I know, for example, that for a Bare Metal Recovery backup, WSBACKUP has to backup all folders on the System volume (and any volume containing system data), so keeping data away from the OS should reduce the amount of data that needs to be backed up. Having said that, what would be the point in doing a BMR backup within a VM when you can backup a VM at the host level, and therefore restore the entire VM without needing to use BMR.

 

It got me wondering what other people are doing when creating partitions for their new virtual servers.

 

Thanks,

 

Bruce.

Edited September 27, 2011 by Bruce123

[AngryTechnician]

I tend to stick to 1 partition per VHD, but the question of whether to partition at all really comes down to the server role. For anything that has the potential to fill the disk unexpectedly (i.e. produces a lot of logging, or stores user data), its good to keep data separate so that disk space exhaustion won't bring the whole server down.

[SYNACK]

The performance argument even with RAID1/5 in real servers is largely moot given the performance of modern arrays. Keep the partitions as seporate VHDs just for segmentation of the OS/DATA so that users can't inadvertantly cook a server by saving too many illegal MP3s on it.

[dhicks]

D: RAID 5 (Data)

 

After reading up about RAID 5 on modern, larger disks, I'd go for RAID 6.

 

However, the performance argument for retaining this convention on virtual servers is a weak (as they are stored on the same storage unit and won't see much, if any, peformance benefit).

 

There's no reason why you can't assign a VM its own dedicated disk block - a whole RAID group to itself - if it needs the performance.

 

 

what would be the point in doing a BMR backup within a VM when you can backup a VM at the host level, and therefore restore the entire VM without needing to use BMR.

 

But if the data and OS were both together, you'd have to restore both when you restored the VM - if that's something large like user files or images that might take a while.