On Thu, Jan 8, 2009 at 2:01 PM, Aldo Foot <lunixer@xxxxxxxxx> wrote: > On Wed, Jan 7, 2009 at 7:16 AM, Patrick O'Callaghan > <pocallaghan@xxxxxxxxx> wrote: >> On Wed, Jan 7, 2009 at 9:33 PM, Rick Stevens <ricks@xxxxxxxx> wrote: >>> >>> Try "lsof | grep nfs" to see if anything has the mountpoint open. If >>> not, try "umount -f /mnt/nfs" as the root user to try a forced umount. >>> >>> Also check to see if the mount command (or /etc/fstab entry) has "hard" >>> specified (that's the default as well). Unless you're really certain >>> about the stability of the network and of the NFS server, I'd recommend >>> you specify "soft" in the mount command (see "man 5 nfs" for details). >> >> That would depend on which is worse, potentially losing data or having >> a client machine hang because the server is (perhaps temporarily) >> unavailable. It depends totally on the specific application scenario. >> To quote nfs(5): >> >> <quote> >> A so-called "soft" timeout can cause silent data corruption in >> certain cases. As such, use the soft option only when client >> responsiveness is more important than data integrity. Using NFS over >> TCP or increasing the value of the retrans option may mitigate some >> of the risks of using the soft option. >> </quote> >> >> IOW there is no "right" answer to this. >> >> poc > > The command "umount -f" fixed my problem. Thanks Rick. > I had tried "umount -k", which works in older RedHat8 > boxes; clearly I've got to re-read the man pages now and then. > > So, it appears a soft mount may be ok for read-only operations but not > ideal for things such as remote X-applicatons or filesystems > such as /home or /var/mail. It's wise to make the distinction between hard > and soft mount --great pointer. Remote X apps don't require NFS per se (though a specific use may). Also, NFS is usually deprecated for mailstores, as in the past it has had persistent problems with file locking, being at bottom a stateless protocol (recent versions may have fixed this, I don't know). Using maildir is a way round this as it avoids locks. poc -- fedora-list mailing list fedora-list@xxxxxxxxxx To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list Guidelines: http://fedoraproject.org/wiki/Communicate/MailingListGuidelines
