NFS share directory

[Dave Olker]

Hi Jesse,

When you say "moved to another location", is the NFS server now using a different IP address? If so, just forcibly tearing down the stale TCP connection between the client and server is not going to cause the filesystem to magically unmount on the client.

The server's current IP address is still going to be stored in the client's mntinfo structure in the kernel so the next time you access that mount point it will use the same IP address. You have to figure out a way to unmount the filesystem, not just rip out the underlying TCP connection.

Since you're running 11.11 (as opposed to 11.23 or 11.31) you don't have the ability to do a forcible unmount. However, you may be able to get the client to unmount the filesystem without rebooting it.

I've written a technical paper that discusses various strategies to manually unmount filesystems in situations like these. The paper is located here:

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

Good luck,

Dave

[Jesse Delk]

Alot of good info on the White paper....easy enough for even me to follow.

The NFS server CT2 has a new IP Address. I made changes wherever I could find them to point to the new ip address of CT2 on CT1.

Cannot umount because I get the :is busy thing.

When trying to do the netstat -in I only get two lan0 lo0. I don't see any that may be pointing to the old ip address (or similar) to do the ifconfig lan# portion of the white paper.

I know I may be rebooting.




Look as though I may have to reboot.

[Dave Olker]

Hi Jesse,

> When trying to do the netstat -in I only get
> two lan0 lo0. I don't see any that may be
> pointing to the old ip address (or similar)
> to do the ifconfig lan# portion of the white
> paper.

The instructions in the technical paper are to log onto the client and use the ifconfig command to create a temporary virtual interface using the old server's IP address. In this case you would be able to assign the IP address to either your physical interface (lan0) or your loopback interface (lo0). It doesn't matter, as long as the hung NFS mount point can suddenly get a response from the IP address it's sending to.

Before rebooting, I'd give this a try.

1) Log into the NFS client
2) Use the ifconfig command to create a virtual interface using the NFS server's old IP address:

# ifconfig lo0:1 up

Hopefully creating the temporary virtual interface will cause the client to stop hanging on the mounted filesystem and a bdf command will return an ESTALE (stale file handle error message) for that NFS mount point. At that point you *might* be able to unmount the filesystem successfully. Try a few times, like in the technical paper, because it might take some time for the client's buffer cache pages to flush.

If you're able to get the filesystem to unmount then remove the virtual IP interface from the loopback interface:

# ifconfig lo0:1 0

Hope this helps,

Dave