On Thu, 19 Apr 2012, Giovanni Tirloni wrote:
> Did you run this command during "the hang" or is it constantly returning
> you that?
It is returning the time out only during the hang; the rest of the time
it works normally.
> If the later, are you blocking UDP on either the server or the client?
No blocking.
> If you don't specify transport protocol, rpcinfo will use whatever is
> defined in the /etc/netconfig database and that's usually UDP.
Using UDP or TCP makes no difference. "rpcinfo -{u,t} host nfs" both give
a timeout during the hang, and work normally during other times.
> - Is it happening at the exact same minute (eg. 2:15, 2:45, 3:15, 3:45).
> This might help you to identify a script/program that follows that schedule.
It is not related to any script that I can find. It is not happening at
_exactly_ the same time all the time, although it is similar within a few
minutes.
> - Is there any configuration different between this server and the others?
> /etc/system, root crontab, etc.
No differences that I can find.
> - When you say everything else BUT NFS is working fine, are pings answered
> properly without increased latency during "the hang" ?
Yes. I can even run an iperf server on the host during the hang, and from
a client I run iperf -c and get normal performance.
> - What about other services? Can you set up a monitoring script connecting
> to some other service (eg. ftp, ls, exit or ssh) and reporting the total
> run time?
No other service appears to be impacted at all.
> - Can you set up a monitoring script running "rpcinfo" on localhost to make
> sure both local and remote communications hang?
Yes, can do.
-Steve