network lock manager (lockd) deadlocked in 'rpcrecv'

[John Hein]

John Hein wrote at 15:51 -0600 on Jul  8, 2009:
 > John Hein wrote at 15:31 -0600 on Jul  8, 2009:
 >  > I have a home directory on FreeBSD 7.2-stable (20090705), amd64.
 >  > It is serving up the directory over nfs (v3, tcp), and now
 >  > I'm seeing lots of 'lockd not responding' on Fedora 10 & 11 systems.
  .
  .
 > Also in dmesg:
 > 
 > NLM: failed to contact remote rpcbind, stat = 5, port = 28416
  .
  .

Here's some good information.  This seems to happen when there are 2
or more Fedora systems trying to access locks via lockd.

Rebooting the Fedora box that has 'lockd not responding' frees
up the deadlocked freebsd lockd.

But _also_ disabling the firewall on the Fedora boxes helps, too.

This doesn't necessarily completely implicate or exonerate
lockd.  But what should lockd do when the remote box asks
for a lock, but doesn't complete the RPC dialog?  Is there
a way we can deal with this problem and not have lockd
deadlock?