I would like to put it a bit blunter: never use NFS on the SAS server, at least not in Linux (we tried both SUSE and RHEL).

IT implemented SAS on NFS on our Linux environment, against our advise.
It was a disaster. When one process was writing a data set to a disk, all other processes that read from that same disk stalled.
and this was not SAS-related, it was easy to replicate:

1. start a dd in one shell that writes a big file to an NFS file system
2. start another shell and while the dd is running, do an ls on that same file system. it takes > 30 seconds before it comes back with the file list.

The NAS system never made it to production. After 2 years IT agreed that we should have a SAN; works great.