# fsfreeze

## NAME



           fsfreeze - suspend access to a filesystem (Ext3/4, ReiserFS, JFS,
           XFS)
    


## SYNOPSIS



           **fsfreeze --freeze** |**--unfreeze** _mountpoint_
    


## DESCRIPTION



           **fsfreeze** suspends or resumes access to a filesystem.
    
           **fsfreeze** halts any new access to the filesystem and creates a
           stable image on disk. **fsfreeze** is intended to be used with
           hardware RAID devices that support the creation of snapshots.
    
           **fsfreeze** is unnecessary for **device-mapper** devices. The
           device-mapper (and LVM) automatically freezes a filesystem on the
           device when a snapshot creation is requested. For more details see
           the dmsetup(8) man page.
    
           The _mountpoint_ argument is the pathname of the directory where the
           filesystem is mounted. The filesystem must be mounted to be frozen
           (see mount(8)).
    
           Note that access-time updates are also suspended if the filesystem
           is mounted with the traditional atime behavior (mount option
           **strictatime** , for more details see mount(8)).
    


## OPTIONS



           **-f** , **--freeze**
               This option requests the specified filesystem to be frozen
               from new modifications. When this is selected, all ongoing
               transactions in the filesystem are allowed to complete, new
               write(2) system calls are halted, other calls which modify the
               filesystem are halted, and all dirty data, metadata, and log
               information are written to disk. Any process attempting to
               write to the frozen filesystem will block waiting for the
               filesystem to be unfrozen.
    
               Note that even after freezing, the on-disk filesystem can
               contain information on files that are still in the process of
               unlinking. These files will not be unlinked until the
               filesystem is unfrozen or a clean mount of the snapshot is
               complete.
    
           **-u** , **--unfreeze**
               This option is used to un-freeze the filesystem and allow
               operations to continue. Any filesystem modifications that were
               blocked by the freeze are unblocked and allowed to complete.
    
           **-h** , **--help**
               Display help text and exit.
    
           **-V** , **--version**
               Display version and exit.
    


## FILESYSTEM SUPPORT



           This command will work only if filesystem supports has support for
           freezing. List of these filesystems include (2016-12-18) **btrfs** ,
           **ext2/3/4** , **f2fs** , **jfs** , **nilfs2** , **reiserfs** , and **xfs**. Previous list may
           be incomplete, as more filesystems get support. If in doubt
           easiest way to know if a filesystem has support is create a small
           loopback mount and test freezing it.
    


## NOTES



           This man page is based on xfs_freeze(8).
    


## AVAILABILITY



           The **fsfreeze** command is part of the util-linux package which can
           be downloaded from Linux Kernel Archive
           <https://www.kernel.org/pub/linux/utils/util-linux/>. This page is
           part of the _util-linux_ (a random collection of Linux utilities)
           project. Information about the project can be found at 
           ⟨https://www.kernel.org/pub/linux/utils/util-linux/⟩. If you have a
           bug report for this manual page, send it to
           util-linux@vger.kernel.org. This page was obtained from the
           project's upstream Git repository
           ⟨git://git.kernel.org/pub/scm/utils/util-linux/util-linux.git⟩ on
           2025-08-11. (At that time, the date of the most recent commit that
           was found in the repository was 2025-08-05.) If you discover any
           rendering problems in this HTML version of the page, or you
           believe there is a better or more up-to-date source for the page,
           or you have corrections or improvements to the information in this
           COLOPHON (which is _not_ part of the original manual page), send a
           mail to man-pages@man7.org
    
    util-linux 2.42-start-521-ec46  2025-01-16                    _FSFREEZE_(8)
    


* * *