Ref: 03250426
Title: IB/2 Configuration with Sun Workstations and NFS
Date: 11/9/87

Copyright 3Com Corporation, 1991.  All rights reserved.

QUESTION:  How do you implement an IB/2 in networks with SUN
workstations using NFS?  We are experiencing difficulties--NFS
reports multiple timeout errors under heavy traffic load.  The
two workstations are two IB/s apart, and the net utilization is
high at 20% on the backbone and 18% on one of the ribs.  When
repeaters are placed in IB locations, there are no errors.

ANSWER:  The IB/2 requires adequate spacing between large
packets.  To assure spacing, you can have the Sun users set
rsize=1024 and wsize=1024, down from the default of 8K packets in
the /etc/fstab file (NFS file systems only).

Sample entry:

  servervax:/src /src nfs rsize=1024,wsize=1024,intr 0 0

Then execute:

  /etc/umount -vat nfs
  /etc/mount -vat nfs

That should solve the problem.

