Re: NFS hang + umount -f: better behaviour requested.

[Neil Brown <neilb@suse.de>]

On Monday August 20, rlpowell@digitalkingdom.org wrote:
> (cc's to me appreciated)
> 
> It would be really, really nice if "umount -f" against a hung NFS
> mount actually worked on Linux.  As much as I hate Solaris, I
> consider it the gold standard in this case: If I say
> "umount -f /mount/that/is/hung" it just goes away, immediately, and
> anything still trying to use it dies (with EIO, I'm told).

Have you tried "umount -l"?   How far is that from your requirements?

Alternately:
   mount --move /problem/path /somewhere/else
   umount -f /somewhere/else
   umount -l /somewhere/else

might be a little closer to what you want.

Though I agree that it would be nice if we could convince all
subsequent requests to a server to fail EIO instead of just the
currently active ones.  I'm not sure that just changing "umount -f" is
the right interface though....  Maybe if all the server handles
appeared in sysfs and have an attribute which you could set to cause
all requests to fail...

NeilBrown