In some cases when a repository has grown large enough to fill up all disk space
or the allocated quota, then
prune might fail to free space.
prune works in
such a way that a repository remains usable no matter at which point the command
is interrupted. However, this also means that
prune requires some scratch
space to work.
In most cases it is sufficient to instruct
prune to remove all packs marked
for removal and use as little scratch space as possible. Note that packs marked
for removal are automatically removed by a prune run once they are old enough.
If you can guarantee that the repository is not used by parallel processes, you
can also use
rustic prune --instant-delete.
To use as little scratch space as possibe, run
rustic prune --max-repack-size 0. This removes all unneeded packs without
repacking partly used packs. Obviously, this can only work if several snapshots
have been removed using
forget before. This then allows the
prune command to
actually remove data from the repository. If the command succeeds, but there is
still little free space, then remove a few more snapshots and run