LXD Backup Strategies

To backup a LXD instance different strategies are available.

Full backup

This requires that the whole /var/lib/lxd folder will be backuped up. Additionally, it is necessary to backup all storage pools as well.

In order to restore the LXD instance the old /var/lib/lxd folder needs to be removed and replaced with the /var/lib/lxd snapshot. All storage pools need to be restored as well.

Secondary LXD

This requires a second LXD instance to be setup and reachable from the LXD instance that is to be backed up. Then, all containers can be copied to the secondary LXD instance for backup.

Container backup and restore

Additionally, LXD maintains a backup.yaml file in each container's storage volume. This file contains all necessary information to recover a given container, such as container configuration, attached devices and storage. This file can be processed by the lxd import command.

Running

lxd import <container-name>

will restore the specified container from its backup.yaml file. This recovery mechanism is mostly meant for emergency recoveries and will try to re-create container and storage database entries from a backup of the storage pool configuration.

Note that the corresponding storage volume for the container must exist and be accessible before the container can be imported. For example, if the container's storage volume got unmounted the user is required to remount it manually.

If any matching database entry for resources declared in backup.yaml is found during import, the command will refuse to restore the container. This can be overridden running

lxd import --force <container-name>

which causes LXD to delete and replace any currently existing db entries.