borg transfer

borg [common options] transfer [options]
options
  -n, --dry-run do not change repository, just check
  --other-repo SRC_REPOSITORY transfer archives from the other repository
  --upgrader UPGRADER use the upgrader to convert transferred data (default: no conversion)

Common options

Archive filters — Archive filters can be applied to repository targets.
  -a PATTERN, --match-archives PATTERN only consider archive names matching the pattern. see “borg help match-archives”.
  --sort-by KEYS Comma-separated list of sorting keys; valid keys are: timestamp, name, id; default is: timestamp
  --first N consider first N archives after other filters were applied
  --last N consider last N archives after other filters were applied
  --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.

Description

This command transfers archives from one repository to another repository. Optionally, it can also upgrade the transferred data.

Suggested use for general purpose archive transfer (not repo upgrades):

# create a related DST_REPO (reusing key material from SRC_REPO), so that
# chunking and chunk id generation will work in the same way as before.
borg --repo=DST_REPO rcreate --other-repo=SRC_REPO --encryption=DST_ENC

# transfer archives from SRC_REPO to DST_REPO
borg --repo=DST_REPO transfer --other-repo=SRC_REPO --dry-run  # check what it would do
borg --repo=DST_REPO transfer --other-repo=SRC_REPO            # do it!
borg --repo=DST_REPO transfer --other-repo=SRC_REPO --dry-run  # check! anything left?

The default is to transfer all archives, including checkpoint archives.

You could use the misc. archive filter options to limit which archives it will transfer, e.g. using the -a option. This is recommended for big repositories with multiple data sets to keep the runtime per invocation lower.

For repository upgrades (e.g. from a borg 1.2 repo to a related borg 2.0 repo), usage is quite similar to the above:

borg --repo=DST_REPO transfer --other-repo=SRC_REPO --upgrader=From12To20

Examples

# 0. Have borg 2.0 installed on client AND server, have a b12 repo copy for testing.

# 1. Create a new "related" repository:
# here, the existing borg 1.2 repo used repokey-blake2 (and aes-ctr mode),
# thus we use repokey-blake2-aes-ocb for the new borg 2.0 repo.
# staying with the same chunk id algorithm (blake2) and with the same
# key material (via --other-repo <oldrepo>) will make deduplication work
# between old archives (copied with borg transfer) and future ones.
# the AEAD cipher does not matter (everything must be re-encrypted and
# re-authenticated anyway), you could also choose repokey-blake2-chacha20-poly1305.
# in case your old borg repo did not use blake2, just remove the "-blake2".
$ borg --repo       ssh://borg2@borgbackup/./tests/b20 rcreate \
       --other-repo ssh://borg2@borgbackup/./tests/b12 -e repokey-blake2-aes-ocb

# 2. Check what and how much it would transfer:
$ borg --repo       ssh://borg2@borgbackup/./tests/b20 transfer --upgrader=From12To20 \
       --other-repo ssh://borg2@borgbackup/./tests/b12 --dry-run

# 3. Transfer (copy) archives from old repo into new repo (takes time and space!):
$ borg --repo       ssh://borg2@borgbackup/./tests/b20 transfer --upgrader=From12To20 \
       --other-repo ssh://borg2@borgbackup/./tests/b12

# 4. Check if we have everything (same as 2.):
$ borg --repo       ssh://borg2@borgbackup/./tests/b20 transfer --upgrader=From12To20 \
       --other-repo ssh://borg2@borgbackup/./tests/b12 --dry-run