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BTRFS-SUBVOLUME(8)               Btrfs Manual               BTRFS-SUBVOLUME(8)

NAME
       btrfs-subvolume - manage btrfs subvolumes
SYNOPSIS
       btrfs subvolume <subcommand> [<args>]
DESCRIPTION
       btrfs subvolume is used to create/delete/list/show btrfs subvolumes and
       snapshots.
SUBVOLUME AND SNAPSHOT
       A subvolume is a part of filesystem with its own and independent
       file/directory hierarchy. Subvolumes can share file extents. A snapshot
       is also subvolume, but with a given initial content of the original
       subvolume.
           Note
           A subvolume in btrfs is not like an LVM logical volume, which is
           block-level snapshot while btrfs subvolumes are file extent-based.
       A subvolume looks like a normal directory, with some additional
       operations described below. Subvolumes can be renamed or moved, nesting
       subvolumes is not restricted but has some implications regarding
       snapshotting.
       A subvolume in btrfs can be accessed in two ways:
       o   like any other directory that is accessible to the user
       o   like a separately mounted filesystem (options subvol or subvolid)
       In the latter case the parent directory is not visible and accessible.
       This is similar to a bind mount, and in fact the subvolume mount does
       exactly that.
       A freshly created filesystem is also a subvolume, called top-level,
       internally has an id 5. This subvolume cannot be removed or replaced by
       another subvolume. This is also the subvolume that will be mounted by
       default, unless the default subvolume has been changed (see subcommand
       set-default).
       A snapshot is a subvolume like any other, with given initial content.
       By default, snapshots are created read-write. File modifications in a
       snapshot do not affect the files in the original subvolume.
SUBCOMMAND
       create [-i <qgroupid>] [<dest>/]<name>
           Create a subvolume <name> in <dest>.
           If <dest> is not given, subvolume <name> will be created in the
           current directory.
           Options
           -i <qgroupid>
               Add the newly created subvolume to a qgroup. This option can be
               given multiple times.
       delete [options] <subvolume> [<subvolume>...]
           Delete the subvolume(s) from the filesystem.
           If <subvolume> is not a subvolume, btrfs returns an error but
           continues if there are more arguments to process.
           The corresponding directory is removed instantly but the data
           blocks are removed later. The deletion does not involve full commit
           by default due to performance reasons (as a consequence, the
           subvolume may appear again after a crash). Use one of the --commit
           options to wait until the operation is safely stored on the media.
           Options
           -c|--commit-after
               wait for transaction commit at the end of the operation
           -C|--commit-each
               wait for transaction commit after deleting each subvolume
       find-new <subvolume> <last_gen>
           List the recently modified files in a subvolume, after <last_gen>
           ID.
       get-default <path>
           Get the default subvolume of the filesystem <path>.
           The output format is similar to subvolume list command.
       list [options] [-G [+|-]<value>] [-C [+|-]<value>]
       [--sort=rootid,gen,ogen,path] <path>
           List the subvolumes present in the filesystem <path>.
           For every subvolume the following information is shown by default.
           ID <ID> top level <ID> path <path> where path is the relative path
           of the subvolume to the top level subvolume. The subvolume's ID may
           be used by the subvolume set-default command, or at mount time via
           the subvolid= option. If -p is given, then parent <ID> is added to
           the output between ID and top level. The parent's ID may be used at
           mount time via the subvolrootid= option.
           Options
           -p
               print parent ID.
           -a
               print all the subvolumes in the filesystem and distinguish
               between absolute and relative path with respect to the given
               <path>.
           -c
               print the ogeneration of the subvolume, aliases: ogen or origin
               generation.
           -g
               print the generation of the subvolume.
           -o
               print only subvolumes below specified <path>.
           -u
               print the UUID of the subvolume.
           -q
               print the parent uuid of subvolumes (and snapshots).
           -R
               print the UUID of the sent subvolume, where the subvolume is
               the result of a receive operation
           -t
               print the result as a table.
           -s
               only snapshot subvolumes in the filesystem will be listed.
           -r
               only readonly subvolumes in the filesystem will be listed.
           -G [+|-]<value>
               list subvolumes in the filesystem that its generation is >=, <
               or = value. '+' means >= value, '-' means <= value, If there is
               neither '+' nor '-', it means = value.
           -C [+|-]<value>
               list subvolumes in the filesystem that its ogeneration is >=,
               <= or = value. The usage is the same to -G option.
           --sort=rootid,gen,ogen,path
               list subvolumes in order by specified items. you can add '+' or
               '-' in front of each items, '+' means ascending, '-' means
               descending. The default is ascending.
               for --sort you can combine some items together by ',', just
               like --sort=+ogen,-gen,path,rootid.
       set-default <id> <path>
           Set the subvolume of the filesystem <path> which is mounted as
           default.
           The subvolume is identified by <id>, which is returned by the
           subvolume list command.
       show <path>
           Show information of a given subvolume in the <path>.
       snapshot [-r] <source> <dest>|[<dest>/]<name>
           Create a writable/readonly snapshot of the subvolume <source> with
           the name <name> in the <dest> directory.
           If only <dest> is given, the subvolume will be named the basename
           of <source>. If <source> is not a subvolume, btrfs returns an
           error. If -r is given, the snapshot will be readonly.
       sync <path> [subvolid...]
           Wait until given subvolume(s) are completely removed from the
           filesystem after deletion. If no subvolume id is given, wait until
           all current deletion requests are completed, but do not wait for
           subvolumes deleted meanwhile. The status of subvolume ids is
           checked periodically.
           Options
           -s <N>
               sleep N seconds between checks (default: 1)
EXIT STATUS
       btrfs subvolume returns a zero exit status if it succeeds. A non-zero
       value is returned in case of failure.
AVAILABILITY
       btrfs is part of btrfs-progs. Please refer to the btrfs wiki
       http://btrfs.wiki.kernel.org for further details.
SEE ALSO
       mkfs.btrfs(8), mount(8), btrfs-quota(8), btrfs-qgroup(8),

Btrfs v4.9.1                      08/06/2017                BTRFS-SUBVOLUME(8)