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mksnap_ffs(8) [freebsd man page]

MKSNAP_FFS(8)						    BSD System Manager's Manual 					     MKSNAP_FFS(8)

mksnap_ffs -- take a file system snapshot SYNOPSIS
mksnap_ffs snapshot_name DESCRIPTION
The mksnap_ffs utility creates a snapshot named snapshot_name. The group ownership of the file is set to ``operator''; the owner of the file remains ``root''. The mode of the snapshot is set to be read- able by the owner or members of the ``operator'' group. EXAMPLES
Create a snapshot of /usr/home file system and mount the snapshot elsewhere: mksnap_ffs /usr/home/snapshot mdconfig -a -t vnode -o readonly -f /usr/home/snapshot mount -o ro /dev/md0 /mnt/ SEE ALSO
chmod(2), chown(8), mdconfig(8), mount(8) HISTORY
The mksnap_ffs utility first appeared in FreeBSD 5.0. CAVEATS
The disk full situation is not handled gracefully and may lead to a system panic when no free blocks are found. Every filesystem can have only up to 20 active snapshots. When this limit is reached, attempting to create more snapshots fails with ENOSPC, and mksnap_ffs reports that it is ``out of space''. BSD
February 14, 2011 BSD

Check Out this Related Man Page

fssnap(1M)                                                System Administration Commands                                                fssnap(1M)

fssnap - create temporary snapshots of a file system SYNOPSIS
fssnap [-F FSType] [-V] -o special_options /mount/point fssnap -d [-F FSType] [-V] /mount/point | dev fssnap -i [-F FSType] [-V] [-o special_options] [/mount/point | dev] DESCRIPTION
The fssnap command creates a stable, read-only snapshot of a file system when given either an active mount point or a special device con- taining a mounted file system, as in the first form of the synopsis. A snapshot is a temporary image of a file system intended for backup operations. While the snapshot file system is stable and consistent, an application updating files when the snapshot is created might leave these files in an internally inconsistent, truncated, or otherwise unusable state. In such a case, the snapshot will contain these partially written or corrupted files. It is a good idea to ensure active applications are suspended or checkpointed and their associated files are also consis- tent during snapshot creation. File access times are not updated while the snapshot is being created. A path to the virtual device that contains this snapshot is printed to standard output when a snapshot is created. OPTIONS
The following options are supported: -d Deletes the snapshot associated with the given file system. -F FSType Specifies the file system type to be used. The FSType should either be specified here or be determined by matching the block special device with an entry in the /etc/vfstab table, or by consulting /etc/default/fs. -i Displays the state of any given FSType snapshot. If a mount-point or device is not given, a list of all snapshots on the system is displayed. When a mount-point or device is specified, detailed information is provided for the specified file system snapshot by default. The format and meaning of this information is file-system dependent. See the FSType-specific fssnap man page for details. -o special_options See the FSType-specific man page for fssnap. -V Echoes the complete command line, but does not execute the command. OPERANDS
The following operands are supported: /mount/point The directory where the file system resides. EXAMPLES
See FSType-specific man pages for examples. EXIT STATUS
The following exit values are returned: 0 Successful completion. >0 An error occurred. FILES
/etc/vfstab Specifies file system type. /etc/default/fs Specifies the default local file system type. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Availability |SUNWcsu | +-----------------------------+-----------------------------+ SEE ALSO
fssnap_ufs(1M), attributes(5) NOTES
This command might not be supported for all FSTypes. SunOS 5.10 11 Aug 2004 fssnap(1M)

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