The
utility is proposed in the
NFS
RPC specification; see
"NFS Version 3 Protocol Specification"
"RFC 1813, Appendix I"
It uses remote procedure calls to remove mount entries from
/var/db/mountdtab
on the remote NFS server.
It is called automatically
without any parameters during startup and shutdown of
the system.
This ensures that
showmount(8)
does not display old and expired entries.
The
utility
is only needed on client side, where
mount_nfs8
adds a mount entry with the current date to
/var/db/mounttab
and
umount(8)
removes the entry again.
The
utility
cares about all remaining entries in this table which result from crashes
or unproper shutdowns.
The options are as follows:
-e expire
All entries which are not actually mounted or older than
expire
(seconds) are removed from
/var/db/mounttab
This may be the case
for DNS changes or long out of service periods.
Default expire time
is 86400 seconds (one day).
-h host
Only remove the specific hostname.
Send a UMNTALL RPC to the NFS server.
-k
Keep entries for existing NFS file systems.
Compare the NFS file systems from
the mounttab against the kernel mountlist and do not send the RPC to
existing mount entries.
Useful during startup of the system.
It may be
possible that there are already mounted NFS file systems, so calling
RPC UMOUNT is not a good idea.
This is the case if the user has rebooted
to 'single user mode' and starts up the system again.
-p path
Only remove the specific mount-path.
Send a UMOUNT RPC to the NFS server.
This option implies the
-host
option.
-v
Verbose, additional information is printed for each processed mounttab
entry.