vSphere 6 NFS 4.1 Gotchas

VMware has added some additional NFS features to v6.  I knew it supported NFS 4.1 as well as 3, but there are some significant ramifications related to this and some gotchas.

  1. vSphere does not support parallel NFS (pNFS)! 
  2. It DOES support multipathing if connecting with NFS 4.1.  What you do is add the multiple NFS target IPs when setting up your NFS mount.
  3. IMPORTANT: This is the biggest gotcha, and something we all need to be aware of.  If your system supports both 4.1 and 3 simultaneously for a mount, you MUST use one or the other for an export used by VMware!  V3 and v4.1 use different locking mechanisms.  Having both enabled for an mount simultaneously and then having different ESXi hosts mounting it with differing versions can corrupt data!!!  Best practice is enable only one of the two protocols for that export, never both.
  4. You can authenticate using Kerberos, which is more secure.

NFS 4.1 support though isn’t all roses.  Here’s what you can’t do…

  • No Storage DRS
  • No SIOC
  • No SRM
  • No vVol
  • No VAAI (bigger deal now that Standard licensing includes VAAI)
  • Must run vSphere Replication 6.1 or higher to use VR to replicate VMs on NFS 4.1 mounts.