I've seen something that behaves like a lockup problem, but is really an NFS hang. This was most troublesome doing ls or df commands when an NFS share was mounted from a SunOS box. Most doc I found recommended the following when connecting to "fast" servers:
mount -t nfs -o rsize=1024,wsize=1024,timeo=14,intr sunbox:/sharename /mountpoint
Dave
-----Original Message-----
From: Pete Huckelba [mailto:redhat stata com]
Sent: Tuesday, November 05, 2002 8:12 AM
To: enigma-list redhat com
Subject: hard locks / high memory
I have three boxes, two problems (one serious problem partially resolved,
one question), all three boxes are running completely up2date, 2.4.18-17.7
kernels.
The first problem manifests itself when the enigma-boxes lock up
completely. Not allowing any keyboard nor mouse input, not responding to
ping, nor any tcp requests. User interaction at the time of lock-up would
be anything from vi'ing a file, to browsing the web. It took forever to
track down the problem since the boxes would crash in the user's office,
but when I tried to replicate the behavior after moving the box to my
office, it behaved like a dream. While it seemed to be completely random,
and viewing the system-logs did not lend much to diagnosing the problem, I
think I may have tracked it down. Both machines were connected to a 10
megabit hub (different hubs, different offices, different segments of the
network), one machine had a win2k box on the hub, the other has a two
Sparc, SunOS 5.8 and SunOS 5.1 boxes on its hub. Sometimes data would move
through eth0 fine, other times the machine would lock. A snipet from one of
the kernel logs shows:
Nov 4 16:42:14 sundown kernel: nfs: server marta OK
Nov 4 16:42:14 sundown last message repeated 3 times
Nov 4 17:09:54 sundown kernel: eepro100: wait_for_cmd_done timeout!
Nov 4 17:10:00 sundown last message repeated 16 times
Nov 4 17:10:04 sundown kernel: nfs: server marta not responding, still trying
Nov 4 17:10:04 sundown kernel: eepro100: wait_for_cmd_done timeout!
Nov 4 17:10:04 sundown kernel: nfs: server marta not responding, still trying
Nov 4 17:10:04 sundown kernel: eepro100: wait_for_cmd_done timeout!
Nov 4 17:10:04 sundown kernel: nfs: server marta not responding, still trying
Nov 4 17:10:04 sundown kernel: eepro100: wait_for_cmd_done timeout!
Nov 4 17:10:04 sundown kernel: nfs: server marta not responding, still trying
Nov 4 17:10:04 sundown kernel: eepro100: wait_for_cmd_done timeout!
Nov 4 17:10:40 sundown last message repeated 25 times
Nov 4 17:11:12 sundown last message repeated 13 times
Nov 4 17:11:14 sundown kernel: NETDEV WATCHDOG: eth0: transmit timed out
Nov 4 17:11:14 sundown kernel: eth0: Transmit timed out: status 0050 0cf0
at 17683/17743 command 000c0000.
Nov 4 17:11:23 sundown kernel: nfs: server marta OK