I have a NetApp FAS 2040 with 24 450GB SAS drives that I am going to use for my virtual environment. I have vSphere 5 Essentials Plus. I have one aggregate and currently there are no volumes yet. The SAN has just been deployed. I have two Dell 710 servers that will be the ESXi hosts and they will connect to the storage via iSCSI. I have heard that NFS is a good choice for storage. My question is should I create one large NFS volume for my virtual servers or several NFS volumes with a few servers in each volume?
This is my first ntime doing this so any recommendations or suggestions are greatly welcomed.
I would build volumes based on backup ad replication policies. If some data needs a daily backup and other data needs every hour then I would create 2 volumes for example. Spindle I/O won't be affected since all volumes are going in the same aggregate.
It may also boil down to the question of what applications are you going to implement (e.g. SQL, Exchange) & whether you are planning to use any SnapManager products?
You are fine to use NFS datastores for your VM boot drives, but disks with application data would normally be provisioned as Raw Device Mappings - with one corner case of SnapManager for SQL, which works happilly with NFS VMDKs (but still volume layout is not that straight forward).
iSCSI presents LUNs (block-based storage) which can be mounted on the vSphere hosts and used as VMFS datastores (or RDMs) or mounted on the guest VMs as iSCSI disks if you want.
NFS presents exports (file-based storage) which can be mounted on the vSphere hosts and used as NFS datastores.
If you want to use RDMs or SnapManager products on your guests you will need iSCSI, for normal datastores NFS is fine. You should put each datastore or LUN in a separate volume.
All VM files on an NFS datastore will be thin provisioned by default, so set the volume guarentee on these volumes to "none" to take advantage of think provisioning at the storage system level as well.