borg-prune

BORG-PRUNE(1) borg backup tool BORG-PRUNE(1)

NAME

   borg-prune - Prune repository archives according to specified rules

SYNOPSIS

   borg [common options] prune [options] [REPOSITORY]

DESCRIPTION

   The prune command prunes a repository by deleting all archives not matching any of the specified retention options.

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

   This command is normally used by automated backup scripts wanting to keep a certain number of historic backups. This retention policy is commonly referred to
   as GFS (Grandfather-father-son) backup rotation scheme.

   Also, prune automatically removes checkpoint archives (incomplete archives left behind by interrupted backup runs) except if the checkpoint is the latest ar‐
   chive (and thus still needed). Checkpoint archives are not considered when comparing archive counts against the retention limits (--keep-X).

   If a prefix is set with -P, then only archives that start with the prefix are considered for deletion and only those archives count towards the totals speci‐
   fied by the rules.  Otherwise, all archives in the repository are candidates for deletion!  There is no automatic distinction between  archives  representing
   different contents. These need to be distinguished by specifying matching prefixes.

   If you have multiple sequences of archives with different data sets (e.g.  from different machines) in one shared repository, use one prune call per data set
   that matches only the respective archives using the -P option.

   The --keep-within option takes an argument of the form "<int><char>", where char is "H", "d", "w", "m", "y". For example, --keep-within 2d means to keep  all
   archives  that were created within the past 48 hours.  "1m" is taken to mean "31d". The archives kept with this option do not count towards the totals speci‐
   fied by any other options.

   A good procedure is to thin out more and more the older your backups get.  As an example, --keep-daily 7 means to keep the latest backup on each day, up to 7
   most  recent days with backups (days without backups do not count).  The rules are applied from secondly to yearly, and backups selected by previous rules do
   not count towards those of later rules. The time that each backup starts is used for pruning purposes. Dates and times are interpreted in the local timezone,
   and  weeks  go  from  Monday to Sunday. Specifying a negative number of archives to keep means that there is no limit. As of borg 1.2.0, borg will retain the
   oldest archive if any of the secondly, minutely, hourly, daily, weekly, monthly, or yearly rules was not otherwise able to meet its  retention  target.  This
   enables the first chronological archive to continue aging until it is replaced by a newer archive that meets the retention criteria.

   The  --keep-last  N option is doing the same as --keep-secondly N (and it will keep the last N archives under the assumption that you do not create more than
   one backup archive in the same second).

   When using --stats, you will get some statistics about how much data was deleted - the "Deleted data" deduplicated size there is most interesting as that  is
   how much your repository will shrink.  Please note that the "All archives" stats refer to the state after pruning.

OPTIONS

   See borg-common(1) for common options of Borg commands.

arguments

   REPOSITORY
          repository to prune

options

   -n, --dry-run
          do not change repository

   --force
          force pruning of corrupted archives, use --force --force in case --force does not work.

   -s, --stats
          print statistics for the deleted archive

   --list output verbose list of archives it keeps/prunes

   --keep-within INTERVAL
          keep all archives within this time interval

   --keep-last, --keep-secondly
          number of secondly archives to keep

   --keep-minutely
          number of minutely archives to keep

   -H, --keep-hourly
          number of hourly archives to keep

   -d, --keep-daily
          number of daily archives to keep

   -w, --keep-weekly
          number of weekly archives to keep

   -m, --keep-monthly
          number of monthly archives to keep

   -y, --keep-yearly
          number of yearly archives to keep

   --save-space
          work slower, but using less space

   -c SECONDS, --checkpoint-interval SECONDS
          write checkpoint every SECONDS seconds (Default: 1800)

Archive filters

   -P PREFIX, --prefix PREFIX
          only consider archive names starting with this prefix. (deprecated)

   -a GLOB, --glob-archives GLOB
          only consider archive names matching the glob. sh: rules apply, see "borg help patterns".

EXAMPLES

   Be careful, prune is a potentially dangerous command, it will remove backup archives.

   The default of prune is to apply to all archives in the repository unless you restrict its operation to a subset of the archives using --glob-archives.  When
   using --glob-archives, be careful to choose a good matching pattern - e.g. do not use "foo*" if you do not also want to match "foobar".

   It is strongly recommended to always run prune -v --list --dry-run ...  first so you will see what it would do without it actually doing anything.

      # Keep 7 end of day and 4 additional end of week archives.
      # Do a dry-run without actually deleting anything.
      $ borg prune -v --list --dry-run --keep-daily=7 --keep-weekly=4 /path/to/repo

      # Same as above but only apply to archive names starting with the hostname
      # of the machine followed by a "-" character:
      $ borg prune -v --list --keep-daily=7 --keep-weekly=4 --glob-archives='{hostname}-*' /path/to/repo
      # actually free disk space:
      $ borg compact /path/to/repo

      # Keep 7 end of day, 4 additional end of week archives,
      # and an end of month archive for every month:
      $ borg prune -v --list --keep-daily=7 --keep-weekly=4 --keep-monthly=-1 /path/to/repo

      # Keep all backups in the last 10 days, 4 additional end of week archives,
      # and an end of month archive for every month:
      $ borg prune -v --list --keep-within=10d --keep-weekly=4 --keep-monthly=-1 /path/to/repo

   There is also a visualized prune example in docs/misc/prune-example.txt.