Hi Scott,
You need to set the permissions on the NFS export so that VMware has permissions to mount it.
3 things you need to d/check...
Check the security level on the volume (from the filerview, goto volumes -> qtrees, from the command line "qtree security"). If ths security is set to NTFS (probably likely), you want to change this to UNIX.
When you change the NFS exports, make sure to allow both root and rw access to all ESX servers. From the filerview there is a wizard that walks you through this, from the command line, edit /etc/exports and make sure "rw=esx1_ip:esx2_ip,root=esx1_ip:esx2_ip" and so on. Then use "exportfs -av" to re-export these (the -v makes it verbose, so should give you some feedback as to what it did).
Then go back to ESX and try again!
There are a couple of good TR's on the NOW site for ESX and NetApp integration, however I can never find it when I need it! Have a look around there, there's some good resources.
