xfs_freeze(8)                                                                                                      xfs_freeze(8)



NAME
       xfs_freeze - suspend access to an XFS filesystem

SYNOPSIS
       xfs_freeze -f | -u mount-point

DESCRIPTION
       xfs_freeze suspends and resumes access to an XFS filesystem (see xfs(5)).

       xfs_freeze halts new access to the filesystem and creates a stable image on disk.  xfs_freeze is intended to be used with
       volume managers and hardware RAID devices that support the creation of snapshots.

       The mount-point argument is the pathname of the directory where the  filesystem  is  mounted.   The  filesystem  must  be
       mounted to be frozen (see mount(8)).

       The  -f flag requests the specified XFS filesystem to be frozen from new modifications.  When this is selected, all ongo-
       ing transactions in the filesystem are allowed to complete, new write 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 com-
       plete.

       The -u flag 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.

       One of -f or -u must be supplied to xfs_freeze.

NOTES
       A  copy  of  a frozen XFS filesystem will usually have the same universally unique identifier (UUID) as the original, and
       thus may be prevented from being mounted.  The XFS nouuid mount option can be used to circumvent this issue.

       In Linux kernel version 2.6.29, the interface which XFS uses to freeze and unfreeze was elevated to the VFS, so that this
       tool can now be used on many other Linux filesystems.

SEE ALSO
       xfs(5), lvm(8), mount(8).



                                                                                                                   xfs_freeze(8)