SQL Server in VMDKs over NFS on NetApp

I'm going to remove this when the full documentation set and some case study architectures are released but here's your starter for ten (University Challenge, look it up!)

FlexVol 1. Create one VMDK per SQL Server Instance. Put the temp DB from each Instance into its own VMDK in that single FlexVol. This is a FlexVol you certainly want on SAS, not SATA backed Flash Cache. You can also put VMDKs in that volume to host your guest page files. You will not be doing any snapshots of that volume whatsoever. ever. No really, never.

FlexVol 2. Create four VMDKs in that volume. One for the Logs for DBs in Full Recovery. One for the DBs, one for SNAPINFO and one for the System Databases. This is your minimum package of volumes per SQL Instance.

IF..... you want a Consistency Group across servers or even Instances on the same server you may put eight (2 x 4) VMDKs, or multiples thereof, into FlexVol 2. Use SnapCreator to generate the synchronized backups.

For the Operating System.

(1) FlexVol 3. Drop your golden OS VMDK into it and SIS Clone it for multiple servers (Use this for Hyper-V)

(2) FlexVol 3. Drop templates into the FlexVol and dedupe the hell out of it. Theoretically you can get over 200 Operating System / SQL Binaries into that one FlexVol and then drop it down so that it uses less space than one VMDK file.

This is based on the principle that all of your databases in a given SQL Instance have similar SLAs. If you have databases with a 15 minute SLA and some with one hour and some with four hour SLAs then you will want to use three SQL Instances. Whether that's one SQL Server name or three of them is entirely up to you.

The use of a database in a VMDK on a FlexVol does not move the granularity of backup; it's still the FlexVol. This isn't a NetApp restriction or unique problem, it's applicable to everyone. If you were doing this on DAS and MS DPM you'd still backup all the databases on the same disk at the same time because the level of granularity is the volume.

Obviously the NAS protocol provides a quantum leap in the flexibility but there are still some VSS/VDS APIs that you have to obey. Marrying one technology with another can make an old SQL hand need a double take but it's a massively popular solution so there are plenty of SQL DBAs and Admins who are completely down with it.

That's your basic end to end architecture. Please check with your local Virtualization or MS Consulting SE at NetApp because this could easily get out of date real quick. As at January 2012 it's good to go.