Missing chunks after exclusive & exhaustive prune job + ongoing backups

[aminetwork2016]

Hello support
my turn to look into missing chunks. Deleted on Jan 16th because of overloaded NAS and backup jobs took hours longer than usual , still running when the scheduled prune -exclusive deleted chunks.

I am not asking how to restore the chunks, they’re gone I beleive. I need to know how to delete snapshots of a given Id: because chunks are missing.
Chunks/storage is a local ext4 disk. If deleting incomplete revisions is not the answer, how can I get back to functionnal operations ? I assume that deleting incomplete revisions will bring me back to a state where missing chunks are not needed anymore, hence not an issue anymore

below, the prune deletion logs, the check OK for revision 540, the check failure for revision 545, and the prune failure deleting rev 545 in exclusive mode
thank you

=== prune logs from Jan 16th ====
I now have 7 chunks missing across several IDs and revisions from Jan 16th.
I have changed existing IDs and ran snapshots of all of these to attempt to recreate chunks.
There are no fossils as I usually delete them during the prune job.
I do not find the actual chunks on my storage.

Log of the prune job that deleted the chunks
./logs/prune-20260116-172803.log:2026-01-16 17:31:44.315 INFO CHUNK_DELETE The chunk b0dfd4ee9072bda74050afab919c5c0717012762003a62d4e97709a4c63de5ff has been permanently removed
./tmp/localhost/all/.duplicacy/logs/prune-log-20260116-172803:Deleted chunk b0dfd4ee9072bda74050afab919c5c0717012762003a62d4e97709a4c63de5ff (exclusive mode)

======= rev 540 ok, not 541 and till now 545 ========
rev 540 is OK , rev 541- > 545 are not.
I would like to delete revs 541,542,543,544,545

540:
2026-01-19 12:13:33.545 INFO STORAGE_SET Storage set to sftp://duplicacy@127.0.0.1/Duplicacy
Enter SSH password:***************2026-01-19 12:13:34.710 INFO SNAPSHOT_CHECK Listing all chunks
2026-01-19 12:13:59.070 INFO SNAPSHOT_CHECK 1 snapshots and 1 revisions
2026-01-19 12:13:59.174 INFO SNAPSHOT_CHECK Total chunk size is 1667G in 378670 chunks
2026-01-19 12:14:01.144 INFO SNAPSHOT_CHECK All chunks referenced by snapshot BriochetteBackup at revision 540 exist

541:
2026-01-19 12:14:07.130 INFO SNAPSHOT_CHECK 1 snapshots and 1 revisions
2026-01-19 12:14:07.186 INFO SNAPSHOT_CHECK Total chunk size is 1667G in 378670 chunks
2026-01-19 12:14:07.563 ERROR DOWNLOAD_CHUNK Chunk 904afa27032255b423b05c493e009351f8994b4e4de039a89a8857c168010e93 can’t be found

542:
2026-01-19 12:14:15.929 INFO SNAPSHOT_CHECK 1 snapshots and 1 revisions
2026-01-19 12:14:15.973 INFO SNAPSHOT_CHECK Total chunk size is 1667G in 378670 chunks
2026-01-19 12:14:18.039 WARN SNAPSHOT_VALIDATE Chunk 9f743b595c45155455b30a9899553779412c283fa882f13fd1db2f8993a7cc3f referenced by snapshot BriochetteBackup at revision 542 does not exist
2026-01-19 12:14:18.180 WARN SNAPSHOT_VALIDATE Chunk c2e03867874fbbeb2a3a23ffecc86dd82ff72722fed7ace8b2d1bb23a32b5002 referenced by snapshot BriochetteBackup at revision 542 does not exist
2026-01-19 12:14:18.187 WARN SNAPSHOT_CHECK Some chunks referenced by snapshot BriochetteBackup at revision 542 are missing
2026-01-19 12:14:18.187 ERROR SNAPSHOT_CHECK Some chunks referenced by some snapshots do not exist in the storage

543:
2026-01-19 12:14:20.229 INFO SNAPSHOT_CHECK 1 snapshots and 1 revisions
2026-01-19 12:14:20.275 INFO SNAPSHOT_CHECK Total chunk size is 1667G in 378670 chunks
2026-01-19 12:14:21.410 WARN SNAPSHOT_VALIDATE Chunk c2e03867874fbbeb2a3a23ffecc86dd82ff72722fed7ace8b2d1bb23a32b5002 referenced by snapshot BriochetteBackup at revision 543 does not exist
2026-01-19 12:14:21.429 WARN SNAPSHOT_VALIDATE Chunk 9f743b595c45155455b30a9899553779412c283fa882f13fd1db2f8993a7cc3f referenced by snapshot BriochetteBackup at revision 543 does not exist
2026-01-19 12:14:21.489 WARN SNAPSHOT_CHECK Some chunks referenced by snapshot BriochetteBackup at revision 543 are missing
2026-01-19 12:14:21.489 ERROR SNAPSHOT_CHECK Some chunks referenced by some snapshots do not exist in the storage

544:
2026-01-19 12:14:21.385 INFO SNAPSHOT_CHECK 1 snapshots and 1 revisions
2026-01-19 12:14:21.465 INFO SNAPSHOT_CHECK Total chunk size is 1667G in 378670 chunks
2026-01-19 12:14:22.224 WARN SNAPSHOT_VALIDATE Chunk 9f743b595c45155455b30a9899553779412c283fa882f13fd1db2f8993a7cc3f referenced by snapshot BriochetteBackup at revision 544 does not exist
2026-01-19 12:14:22.243 WARN SNAPSHOT_VALIDATE Chunk c2e03867874fbbeb2a3a23ffecc86dd82ff72722fed7ace8b2d1bb23a32b5002 referenced by snapshot BriochetteBackup at revision 544 does not exist
2026-01-19 12:14:22.245 WARN SNAPSHOT_CHECK Some chunks referenced by snapshot BriochetteBackup at revision 544 are missing
2026-01-19 12:14:22.245 ERROR SNAPSHOT_CHECK Some chunks referenced by some snapshots do not exist in the storage

545:
2026-01-19 12:15:00.542 INFO SNAPSHOT_CHECK 1 snapshots and 1 revisions
2026-01-19 12:15:00.619 INFO SNAPSHOT_CHECK Total chunk size is 1667G in 378670 chunks
2026-01-19 12:15:03.126 WARN SNAPSHOT_VALIDATE Chunk 9f743b595c45155455b30a9899553779412c283fa882f13fd1db2f8993a7cc3f referenced by snapshot BriochetteBackup at revision 545 does not exist
2026-01-19 12:15:03.187 WARN SNAPSHOT_VALIDATE Chunk c2e03867874fbbeb2a3a23ffecc86dd82ff72722fed7ace8b2d1bb23a32b5002 referenced by snapshot BriochetteBackup at revision 545 does not exist
2026-01-19 12:15:03.199 WARN SNAPSHOT_CHECK Some chunks referenced by snapshot BriochetteBackup at revision 545 are missing
2026-01-19 12:15:03.199 ERROR SNAPSHOT_CHECK Some chunks referenced by some snapshots do not exist in the storage

Attempt to delete rev 545:
-log prune -id BriochetteBackup -r 545 -exclusive
2026-01-19 14:43:55.156 INFO SNAPSHOT_DELETE Deleting snapshot BriochetteBackup at revision 545
2026-01-19 14:44:12.601 ERROR DOWNLOAD_CHUNK Chunk 904afa27032255b423b05c493e009351f8994b4e4de039a89a8857c168010e93 can’t be found

[Droolio]

@aminetwork2016

still running when the scheduled prune -exclusive deleted chunks

You should never, ever, do this. -exclusive should only be run manually, for a specific purpose of immediate clean-up. Scheduling that command is asking for trouble.

@aminetwork2016

I have changed existing IDs and ran snapshots of all of these to attempt to recreate chunks.

That’s a good strategy and about the best you can do.

@aminetwork2016

There are no fossils as I usually delete them during the prune job.

Again, don’t do this. Not doing fossil collection bypasses a very important safety mechanism - you normally shouldn’t have reason to use -exclusive, unless dealing with imminent disk space issues for example. You’re not saving on any disk space by doing it (if you run a tight prune policy, they’ll get deleted anyway on the second run, between backups).

Anyway…

You’ve already done the best to replace those chunks.

One other thing you can try before a final clean-up is to run check -fossils -resurrect (in case you had previous fossils from before and didn’t also use -exhaustive).

The prune logs can get a little spammy so filter out what you need:

grep "WARN SNAPSHOT_CHECK" prune-log-20260116-172803.log

These are the important lines. You’ll have to manually delete the mentioned revisions on the storage for each ID.

[aminetwork2016]

oh yes - haem- I now get the fossil thing ^^ just, how do they get ever deleted ? using ‘prune’ when needed, or are they automatically deleted at some stage by the software ?

Thank you!