Provided by: sfs-server_0.8-0+pre20060720.1-1.1_i386
funmount - forcibly unmount a file system
funmount forcibly attempts to unmount the file system mounted on path.
It is roughly equivalent to running umount -f path. However, on most
operating systems the umount command does a great deal more than simply
execute the unmount system call--for instance it may attempt to read
the attributes of the file system being unmounted and/or contact a
remote NFS server to notify it of the unmount operation. These extra
actions make umount hang when a remote NFS server is unavailable or a
loopback server has crashed, which in turn causes the client to become
ever more wedged. funmount can avoid such situations when you are try‐
ing to salvage a machine with bad NFS mounts without rebooting it.
SFS will get very confused if you ever unmount file systems from
beneath it. SFS’s nfsmounter program tries to clean up the mess if the
client software ever crashes. Running funmount will generally only
make things worse by confusing nfsmounter.
dirsearch(1), newaid(1), rex(1), sfsagent(1), sfskey(1), ssu(1),
sfs_config(5), sfs_hosts(5), sfs_srp_params(5), sfs_users(5),
sfsauthd_config(5), sfscd_config(5), sfsrosd_config(5), sfsrwsd_con‐
fig(5), sfssd_config(5), sfs_environ(7), nfsmounter(8), sfsauthd(8),
sfscd(8), sfsrosd(8), sfsrwcd(8), sfsrwsd(8), sfssd(8), vidb(8)
The full documentation for SFS is maintained as a Texinfo manual. If
the info and SFS programs are properly installed at your site, the com‐
mand info SFS should give you access to the complete manual.
For updates, documentation, and software distribution, please see the
SFS website at http://www.fs.net/.
If /a is a mount point, and /a/b is another mount point, unmounting /a
before /a/b will cause the latter file system to become ‘‘lost.’’ Once
a file system is lost, there is no way to unmount it without rebooting.
Worse yet, on some operating systems, commands such as df may hang
because of a lost file system.
Many operating systems will not let you unmount a file system (even
forcibly) if a process is using the file system’s root directory (for
instance as a current working directory). Under such circumstances,
funmount may fail. To unmount the file system you must find and kill
whatever process is using the directory. Utilities such as fstat and
lsof may be helpful for identifying processes with a particular file