gregrwm wrote at about 19:05:18 -0500 on Tuesday, June 14, 2022: > offhand i'm not really seeing why an interrupt would result in the loss of > a prior backup directory. i'd be surprised to learn that a prior backup is > ever moved or renamed and thus subject to loss if interrupted, but what > else could it be? if an existing backup directory is ever renamed or moved > i would consider that a design flaw worth correcting. i would think it > preferable that once a backup directory gets it's number, it keeps it for > it's entire lifetime, no renames, no moves.
It's not surprising how it happens... BackupPC4 (in contrast to BackupPC3) uses forward deltas. Loosely speaking, one of the first thing it does when making a new backup is to essentially renumber the old backup as the new backup and then as files are added/changed/deleted from the new backup, add those as deltas to the previously newest backup (in turn older backups may be deltas to that from earlier backups). So, if the current/new backup is irretrievably corrupted, then all earlier backups that are deltas to it are non-recoverable as you found out. The question in your case (and in rare cases I have encountered myself when similarly interrupting backups) is why is the newest/current backup corrupted and/or why can't it be unwound back to the previous backup when the backup is interrupted. Hope this helps (without butchering how BackupPC really works :) Jeff _______________________________________________ BackupPC-users mailing list BackupPC-users@lists.sourceforge.net List: https://lists.sourceforge.net/lists/listinfo/backuppc-users Wiki: https://github.com/backuppc/backuppc/wiki Project: https://backuppc.github.io/backuppc/
