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 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:

       •   like any other directory that is accessible to the user

       •   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 in the background. The command returns immediately. See btrfs
           subvolume sync how to wait until the subvolume gets completely removed.

           The deletion does not involve full transaction 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 device.

           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.

           -v|--verbose
               verbose output of operations.

       find-new <subvolume> <last_gen>
           List the recently modified files in a subvolume, after <last_gen>
           generation.

       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> gen <generation> top level <ID> path <path>

           where ID is subvolume’s id, gen is an internal counter which is updated
           every transaction, top level is the same as parent subvolume’s id, and 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.

           Options

           Path filtering

               -o
                   print only subvolumes below specified <path>.

               -a
                   print all the subvolumes in the filesystem and distinguish between
                   absolute and relative path with respect to the given <path>.

           Field selection

               -p
                   print the parent ID (parent here means the subvolume which contains
                   this subvolume).

               -c
                   print the ogeneration of the subvolume, aliases: ogen or origin
                   generation.

               -g
                   print the generation of the subvolume (default).

               -u
                   print the UUID of the subvolume.

               -q
                   print the parent UUID of the subvolume (parent here means subvolume
                   of which this subvolume is a snapshot).

               -R
                   print the UUID of the sent subvolume, where the subvolume is the
                   result of a receive operation.

           Type filtering

               -s
                   only snapshot subvolumes in the filesystem will be listed.

               -r
                   only readonly subvolumes in the filesystem will be listed.

               -d
                   list deleted subvolumes that are not yet cleaned.

           Other

               -t
                   print the result as a table.

           Sorting

               -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 [<subvolume>|<id> <path>]
           Set the default subvolume for the (mounted) filesystem.

           Set the default subvolume for the (mounted) filesystem at <path>. This will
           hide the top-level subvolume (i.e. the one mounted with subvol=/ or
           subvolid=5). Takes action on next mount.

           There are two ways how to specify the subvolume, by <id> or by the
           <subvolume> path. The id can be obtained from btrfs subvolume list, btrfs
           subvolume show or btrfs inspect-internal rootid.

       show [options] <path>
           Show more information about subvolume <path> regarding UUIDs, times,
           generations, flags and related snapshots.

               /mnt/btrfs/subvolume
                       Name:                   subvolume
                       UUID:                   5e076a14-4e42-254d-ac8e-55bebea982d1
                       Parent UUID:            -
                       Received UUID:          -
                       Creation time:          2018-01-01 12:34:56 +0000
                       Subvolume ID:           79
                       Generation:             2844
                       Gen at creation:        2844
                       Parent ID:              5
                       Top level ID:           5
                       Flags:                  -
                       Snapshot(s):

           Options

           -r|--rootid
               rootid of the subvolume.

           -u|--uuid
               UUID of the subvolume.

       snapshot [-r|-i <qgroupid>] <source> <dest>|[<dest>/]<name>
           Create a 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.

           Options

           -r
               Make the new snapshot read only.

           -i <qgroupid>
               Add the newly created subvolume to a qgroup. This option can be given
               multiple times.

       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 in the
           meantime.

           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 v4.20.1                          01/23/2019                    BTRFS-SUBVOLUME(8)

usage: btrfs subvolume <command> <args>

    btrfs subvolume create [-i <qgroupid>] [<dest>/]<name>
        Create a subvolume
    btrfs subvolume delete [options] <subvolume> [<subvolume>...]
        Delete subvolume(s)
    btrfs subvolume list [options] <path>
        List subvolumes and snapshots in the filesystem.
    btrfs subvolume snapshot [-r] [-i <qgroupid>] <source> <dest>|[<dest>/]<name>
        Create a snapshot of the subvolume
    btrfs subvolume get-default <path>
        Get the default subvolume of a filesystem
    btrfs subvolume set-default <subvolume>
    btrfs subvolume set-default <subvolid> <path>
        Set the default subvolume of the filesystem mounted as default.
    btrfs subvolume find-new <path> <lastgen>
        List the recently modified files in a filesystem
    btrfs subvolume show [options] <path>
        Show more information about the subvolume (UUIDs, generations, times, snapshots)
    btrfs subvolume sync <path> [<subvol-id>...]
        Wait until given subvolume(s) are completely removed from the filesystem.

manage subvolumes: create, delete, list, etc