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:
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] <[mkfs.btrfs(8), mount(8), btrfs-quota(8), btrfs-qgroup(8),
Btrfs v5.7 07/02/2020 BTRFS-SUBVOLUME(8)