Upgrading the repository format version

Repositories created using earlier rustic (or restic) versions use an older repository format version and have to be upgraded to allow using all new features. Upgrading must be done explicitly as a newer repository version increases the minimum rustic version required to access the repository. For example the repository format version 2 is only readable using rustic 0.2.0 or newer.

Upgrading to repo version 2 is a two step process: first run config --set-version 2 which will upgrade the repository version. After the migration is complete, run prune to compress the repository metadata. To limit the amount of data rewritten in at once, you can use the prune --max-repack-size size parameter, see :ref:customize-pruning for more details.

File contents stored in the repository will not be rewritten, data from new backups will be compressed. Over time more and more of the repository will be compressed. To speed up this process and compress all not yet compressed data, you can run prune --repack-uncompressed.