Ubuntu Manpage: borg-prune - Prune repository archives according to specified rules

Provided by: borgbackup2_2.0.0b5-1_amd64

NAME

       borg-prune - Prune repository archives according to specified rules

SYNOPSIS

       borg [common options] prune [options]

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 archive (and thus still
needed). Checkpoint archives are not considered when comparing archive counts against the
retention limits (--keep-X).

If you use --match-archives (-a), then only archives that match the pattern are considered
for deletion and only those archives count towards the totals specified 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 globs.

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 --match-archives (-a) 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 specified 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 of the system where borg prune runs, 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.

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

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

Archive filters
-a PATTERN, --match-archives PATTERN
only consider archive names matching the pattern. see "borg help match-archives".

--oldest TIMESPAN
consider archives between the oldest archive's timestamp and (oldest + TIMESPAN),
e.g. 7d or 12m.

--newest TIMESPAN
consider archives between the newest archive's timestamp and (newest - TIMESPAN),
e.g. 7d or 12m.

--older TIMESPAN
consider archives older than (now - TIMESPAN), e.g. 7d oder 12m.

--newer TIMESPAN
consider archives newer than (now - TIMESPAN), e.g. 7d or 12m.

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 -a / --glob-archives.  When using -a, be
       careful to choose a good pattern - e.g. do not use a prefix "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

          # 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 -a '{hostname}-*'
          # actually free disk space:
          $ borg compact

          # 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

          # 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

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

AUTHOR