borg recreate

borg [common options] recreate [options] [REPOSITORY_OR_ARCHIVE] [PATH...]
positional arguments
  REPOSITORY_OR_ARCHIVE repository/archive to recreate
  PATH paths to recreate; patterns are supported
optional arguments
  --list output verbose list of items (files, dirs, …)
  --filter STATUSCHARS only display items with the given status characters (listed in borg create –help)
  -n, --dry-run do not change anything
  -s, --stats print statistics at end

Common options

Exclusion options
  -e PATTERN, --exclude PATTERN exclude paths matching PATTERN
  --exclude-from EXCLUDEFILE read exclude patterns from EXCLUDEFILE, one per line
  --pattern PATTERN experimental: include/exclude paths matching PATTERN
  --patterns-from PATTERNFILE experimental: read include/exclude patterns from PATTERNFILE, one per line
  --exclude-caches exclude directories that contain a CACHEDIR.TAG file (http://www.brynosaurus.com/cachedir/spec.html)
  --exclude-if-present NAME exclude directories that are tagged by containing a filesystem object with the given NAME
  --keep-exclude-tags, --keep-tag-files if tag objects are specified with --exclude-if-present, don’t omit the tag objects themselves from the backup archive
Archive options
  --target TARGET create a new archive with the name ARCHIVE, do not replace existing archive (only applies for a single archive)
  -c SECONDS, --checkpoint-interval SECONDS write checkpoint every SECONDS seconds (Default: 1800)
  --comment COMMENT add a comment text to the archive
  --timestamp TIMESTAMP manually specify the archive creation date/time (UTC, yyyy-mm-ddThh:mm:ss format). alternatively, give a reference file/directory.
  -C COMPRESSION, --compression COMPRESSION select compression algorithm, see the output of the “borg help compression” command for details.
  --recompress MODE recompress data chunks according to --compression. MODE if-different: recompress if current compression is with a different compression algorithm (the level is not considered). MODE always: recompress even if current compression is with the same compression algorithm (use this to change the compression level). MODE never (default): do not recompress.
  --chunker-params PARAMS specify the chunker parameters (CHUNK_MIN_EXP, CHUNK_MAX_EXP, HASH_MASK_BITS, HASH_WINDOW_SIZE) or default to use the current defaults. default: 19,23,21,4095

Description

Recreate the contents of existing archives.

This is an experimental feature. Do not use this on your only backup.

Important: Repository disk space is not freed until you run borg compact.

--exclude, --exclude-from, --exclude-if-present, --keep-exclude-tags, and PATH have the exact same semantics as in “borg create”. If PATHs are specified the resulting archive will only contain files from these PATHs.

Note that all paths in an archive are relative, therefore absolute patterns/paths will not match (--exclude, --exclude-from, PATHs).

--recompress allows one to change the compression of existing data in archives. Due to how Borg stores compressed size information this might display incorrect information for archives that were not recreated at the same time. There is no risk of data loss by this.

--chunker-params will re-chunk all files in the archive, this can be used to have upgraded Borg 0.xx or Attic archives deduplicate with Borg 1.x archives.

USE WITH CAUTION. Depending on the PATHs and patterns given, recreate can be used to permanently delete files from archives. When in doubt, use --dry-run --verbose --list to see how patterns/PATHS are interpreted.

The archive being recreated is only removed after the operation completes. The archive that is built during the operation exists at the same time at “<ARCHIVE>.recreate”. The new archive will have a different archive ID.

With --target the original archive is not replaced, instead a new archive is created.

When rechunking (or recompressing), space usage can be substantial - expect at least the entire deduplicated size of the archives using the previous chunker (or compression) params.

If you recently ran borg check –repair and it had to fix lost chunks with all-zero replacement chunks, please first run another backup for the same data and re-run borg check –repair afterwards to heal any archives that had lost chunks which are still generated from the input data.

Important: running borg recreate to re-chunk will remove the chunks_healthy metadata of all items with replacement chunks, so healing will not be possible any more after re-chunking (it is also unlikely it would ever work: due to the change of chunking parameters, the missing chunk likely will never be seen again even if you still have the data that produced it).

Examples

# Make old (Attic / Borg 0.xx) archives deduplicate with Borg 1.x archives.
# Archives created with Borg 1.1+ and the default chunker params are skipped
# (archive ID stays the same).
$ borg recreate /mnt/backup --chunker-params default --progress

# Create a backup with little but fast compression
$ borg create /mnt/backup::archive /some/files --compression lz4
# Then compress it - this might take longer, but the backup has already completed,
# so no inconsistencies from a long-running backup job.
$ borg recreate /mnt/backup::archive --recompress --compression zlib,9

# Remove unwanted files from all archives in a repository.
# Note the relative path for the --exclude option - archives only contain relative paths.
$ borg recreate /mnt/backup --exclude home/icke/Pictures/drunk_photos

# Change archive comment
$ borg create --comment "This is a comment" /mnt/backup::archivename ~
$ borg info /mnt/backup::archivename
Name: archivename
Fingerprint: ...
Comment: This is a comment
...
$ borg recreate --comment "This is a better comment" /mnt/backup::archivename
$ borg info /mnt/backup::archivename
Name: archivename
Fingerprint: ...
Comment: This is a better comment
...