# snapshot directory on backed up partition
snapshot_dir .snapshots
# snapshot name format <name>.YYYYmmddTHHMM
timestamp_format long
# zstd compression for backup transfer
stream_compress zstd
# path to log
transaction_log /var/log/btrbk.log
# stream buffer size
stream_buffer 256m
# the daily backup is the first one after midnight
preserve_hour_of_day 0
# Monday is the first day of week
preserve_day_of_week monday
# preserve all temporary snapshots for at least one day
snapshot_preserve_min 1d
# preserve 14 latest daily, 8 weekly, 6 monthly, 1 annual snapshots
snapshot_preserve 14d 8w 6m 1y
# do not preserve temporary snapshots
target_preserve_min no
# preserve 6 latest daily, 4 weekly, 6 monthly, 1 annual snapshots
target_preserve 6d 4w 6m 1y
# preserve all snapshot archive
archive_preserve_min all
# exclude
archive_exclude /swap
# root partition
volume /
# backup at /mnt/backup/
target /mnt/backup/my_device
# backup main partition
subvolume .
# partition name in snapshot rootfs
snapshot_name rootfs
That is if you do NOT boot from a subvolume.
https://digint.ch/btrbk/doc/faq.html