Backing up and restoring Btrfs subvolumes

You can back up or restore, or archive and retrieve, Btrfs subvolumes by using the backup-archive client incremental, selective, restore, archive, and retrieve commands.

1. List the subvolumes and determine their IDs.

   btrfs subvolume list /btreefs1
    ID 256 top level 5 path @
    ID 262 top level 5 path @/btreefs1_sub1

2. Make the directory to use as the mount point for the subvolume.

    mkdir /btreefs1_sub1 

3. Mount the subvolume. For example, to mount the subvolume on device sdb1 at /btreefs1_sub1, use the following syntax: mount -t btrfs -o subvolid=262 /dev/sdb1 /btreefs1_sub1

   Protect or recover the subvolume by using one or more of the following operations:

   Operation	Command
   Back up a subvolume	Both incremental and selective backups are supported. dsmc incr /btreefs1_sub1 dsmc sel /btreefs1_sub1/ -subdir=yes
   Restore a subvolume	dsmc restore /btreefs1_sub1/ -subdir=yes -replace=yes
   Archive a subvolume	dsmc archive /btreefs1_sub1/ -subdir=yes
   Retrieve a subvolume	dsmc retrieve /btreefs1_sub1/ -subdir=yes -replace=yes
   Back up a Btrfs subvolume snapshot	Create the subvolume snapshot. Use the btrfs subvolume snapshot command. The snapshot directory that is specified in this example is the /btreefs1/btreefs1_sub1_snap directory, for the subvolume named btreefs1_sub1. btrfs subvolume snapshot /btreefs1/btreefs1_sub1 /btreefs1/btreefs1_sub1_snap Issue the backup-archive client incremental command. Specify the snapshot root option and the location of the Btrfs snapshot. dsmc incr /btreefs1_sub1 -snapshotroot=/btreefs1 /btreefs1_sub1_snap