NFS filesystem is hung and I cannot unmount it

[Fern H2O]

Hey Everyone,

Here's My Problem:
3 servers
SES: where actual FS /trans resides
SEP & SEQ: have /trans NFS mounted on them
Now SEP is working fine but this morning we started having problem with SEQ. It appears that the NFS mount point /trans is HUNG! When i do a BDF, it just freezes. If i do fuser -cu /trans, it also freezes. I try to stop nfs using nfs.core, nfs.client and nfs.server stop script and they all work but when i do nfs.client server it says:

umountall: umount : has failed.
umountall: diagnostics from umount
nfs umount: nfs_unmount: /trans: is busy
umount: return error 1.

I've run out of thing to try out. Please Help!!

[Steven E. Protter]

Shalom,

Ideas:
Drastic: reboot the NFS server. Then stop/start the clients, and nfs.core if needed.

The second part of my previous answer might be enough, but I think you already tried that.

Check the logs in the NFS server, it might help.

SEP

[Fern H2O]

Rebooting server is not an option...

[A. Clay Stephenson]

If you are running 11.23 or 11.31, the -f option has been added to umount to forcibly unmount an NFS filesystem otherwise this behavior is normal and expected. The fix is to fix the NFS server. If you choose to use NFS, you need to understand the consequnces of that decision.

[Fern H2O]

Yes, but like I said, another server who also has the same exact NFS FS mount on it works, so i'm guessing the problem is with the client not the server..

[V. Nyga]

Hi,

a 'ping SES' works? Login form SEQ works?

Normally if SES is up and visible, there should me no problem for SEQ to find it.

Have you checked SES for the rights?
Have you tried an re-exportfs?

Have you already made a search in this forum?
Dave Olker is the nfs guru, I think he had already posted some tests for such a case.

Volkmar

[A. Clay Stephenson]

Here is Dave's cookbook for systems w/o umount -f --- but it doesn't work everytime.

http://docs.hp.com/en/3929/ForciblyUnmountingNFSFilesystems.pdf

Just because another client can access the NFS server doesn't mean that you don't have problems. For example, you may have something as trivial as a hostname resolution problem.