1xfs_freeze(8) System Manager's Manual xfs_freeze(8)
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6 xfs_freeze - suspend access to an XFS filesystem
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9 xfs_freeze -f | -u mount-point
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12 xfs_freeze suspends and resumes access to an XFS filesystem (see
13 xfs(5)).
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15 xfs_freeze halts new access to the filesystem and creates a stable
16 image on disk. xfs_freeze is intended to be used with volume managers
17 and hardware RAID devices that support the creation of snapshots.
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19 The mount-point argument is the pathname of the directory where the
20 filesystem is mounted. The filesystem must be mounted to be frozen
21 (see mount(8)).
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23 The -f flag requests the specified XFS filesystem to be frozen from new
24 modifications. When this is selected, all ongoing transactions in the
25 filesystem are allowed to complete, new write system calls are halted,
26 other calls which modify the filesystem are halted, and all dirty data,
27 metadata, and log information are written to disk. Any process
28 attempting to write to the frozen filesystem will block waiting for the
29 filesystem to be unfrozen.
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31 Note that even after freezing, the on-disk filesystem can contain
32 information on files that are still in the process of unlinking. These
33 files will not be unlinked until the filesystem is unfrozen or a clean
34 mount of the snapshot is complete.
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36 The -u flag is used to un-freeze the filesystem and allow operations to
37 continue. Any filesystem modifications that were blocked by the freeze
38 are unblocked and allowed to complete.
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40 One of -f or -u must be supplied to xfs_freeze.
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43 A copy of a frozen XFS filesystem will usually have the same univer‐
44 sally unique identifier (UUID) as the original, and thus may be pre‐
45 vented from being mounted. The XFS nouuid mount option can be used to
46 circumvent this issue.
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48 In Linux kernel version 2.6.29, the interface which XFS uses to freeze
49 and unfreeze was elevated to the VFS, so that this tool can now be used
50 on many other Linux filesystems.
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53 xfs(5), lvm(8), mount(8).
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57 xfs_freeze(8)