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

Provided by: borgbackup2_2.0.0b19-1_amd64

NAME

       borg-prune - Prune repository archives according to specified rules

SYNOPSIS

       borg [common options] prune [options] [NAME]

DESCRIPTION

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

Important:

• The prune command will only mark archives for deletion ("soft-deletion"), repository disk space is not
freed until you run borg compact.

• You can use borg undelete to undelete archives, but only 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
<https://en.wikipedia.org/wiki/Backup_rotation_scheme#Grandfather-father-son>

(Grandfather-father-son) backup rotation scheme.

The recommended way to use prune is to give the archive series name to it via the NAME argument (assuming
you have the same name for all archives in a series). Alternatively, you can also 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 series of archives with different data sets (e.g. from different machines) in one
shared repository, use one prune call per series.

The --keep-within option takes an argument of the form "<int><char>", where char is "y", "m", "w", "d",
"H", "M", or "S". For example, --keep-within 2d means to keep all archives that were created within the
past 2 days. "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.

Borg will retain the oldest archive if any of the secondly, minutely, hourly, daily, weekly, monthly,
quarterly, 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-13weekly and --keep-3monthly rules are two different strategies for keeping archives every
quarter year.

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).

You can influence how the --list output is formatted by using the --short option (less wide output) or by
giving a custom format using --format (see the borg repo-list description for more details about the
format string).

OPTIONS

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

arguments
NAME specify the archive name

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

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

--short
use a less wide archive part format

--list-pruned
output verbose list of archives it prunes

--list-kept
output verbose list of archives it keeps

--format FORMAT
specify format for the archive part (default: "{archive:<36} {time} [{id}]")

--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

--keep-13weekly
number of quarterly archives to keep (13 week strategy)

--keep-3monthly
number of quarterly archives to keep (3 month strategy)

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

Archive filters
-a PATTERN, --match-archives PATTERN
only consider archives matching all patterns. 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 or 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.

       The recommended way to name archives (with borg create) is to use the identical  archive  name  within  a
       series  of archives. Then you can simply give that name to prune also, so it operates just on that series
       of archives.

       Alternatively, you can use -a / --match-archives to do a match on the archive names  to  select  some  of
       them.   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.

       Don't forget to run borg compact -v after prune to actually free disk space.

          # 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

          # Similar as above but only apply to the archive series named '{hostname}':
          $ borg prune -v --list --keep-daily=7 --keep-weekly=4 '{hostname}'

          # Similar as above but 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 'sh:{hostname}-*'

          # 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