pruning your backups

Over time, borg will continue to simply add to your backups without ever deleting anything. This is not the goal for most people and that's why pruning exists. Borg will remove old backups as per the schedule you define so that you aren't buying an endless amount of backup storage but you still have enough to stay protected. You should consult the borg documentation for more information on this feature.

where to set it

Your pruning options are in the seafbackup.details file in the setting borgPruneSettings. By default, it looks like this:

borgPruneSettings="--keep-within=7d --keep-daily=30 --keep-weekly=12 --keep-monthly=-1"

This is what I use and I find it's a nice balance for most SOHO setups. It tells borg the following:

Keep ALL backups no matter if they are automated or manual or made for any conceivable reason as long as they occurred in the last 7 days
Keep 30 days worth of daily (i.e. once-per-day) backups
Keep 12 weeks of end-of-week backups
Keep an infinite amount of end-of-month backups

Feel free to customize this to your needs, but I think this is a safe starting point for lots of implementations.

disable pruning

If you want to use a different backup management solution or want to do things manually, you can easily disable backup pruning altogether. In your seafbackup.details file, simply set the borgPruneSettings variable to be empty like any of these options:

# option 1
borgPruneSettings=

# option 2
borgPruneSettings=""