---
name: "funmount"
section: "8"
platform: "linux"
package: "sfs-server"
version: "1:0.8-0+pre20060720.1-1"
release: "Debian 4.0 (Etch)"
platforms: ["linux"]
url: "https://new.carta.tech/funmount"
---

# funmount(8)

forcibly unmount a file system

## NAME

funmount - forcibly unmount a file system

## SYNOPSIS

funmount *path*

## DESCRIPTION

**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 trying to salvage a machine with bad NFS mounts without rebooting it.

## CAVEATS

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**.

## SEE ALSO

[*dirsearch*(1)](/dirsearch/1.md), [*newaid*(1)](/newaid/1.md), [*rex*(1)](/rex/1.md), [*sfsagent*(1)](/sfsagent/1.md), [*sfskey*(1)](/sfskey/1.md), [*ssu*(1)](/ssu/1.md), *sfs\_config*(5), [*sfs\_hosts*(5)](/sfs_hosts/5.md), [*sfs\_srp\_params*(5)](/sfs_srp_params/5.md), [*sfs\_users*(5)](/sfs_users/5.md), [*sfsauthd\_config*(5)](/sfsauthd_config/5.md), [*sfscd\_config*(5)](/sfscd_config/5.md), *sfsrosd\_config*(5), [*sfsrwsd\_config*(5)](/sfsrwsd_config/5.md), [*sfssd\_config*(5)](/sfssd_config/5.md), [*sfs\_environ*(7)](/sfs_environ/7.md), *nfsmounter*(8), [*sfsauthd*(8)](/sfsauthd/8.md), [*sfscd*(8)](/sfscd/8.md), *sfsrosd*(8), *sfsrwcd*(8), [*sfsrwsd*(8)](/sfsrwsd/8.md), [*sfssd*(8)](/sfssd/8.md), [*vidb*(8)](/vidb/8.md)

The full documentation for **SFS** is maintained as a Texinfo manual.  If the **info** and **SFS** programs are properly installed at your site, the command **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/*.

## BUGS

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 system open.

## AUTHOR

sfsdev@redlab.lcs.mit.edu