Deduplication between repositories with different chunker parameters

I have an older repository that is not compressed, and a newer one with compression enabled. I want to use

restic -r new-repo copy —from-repo old-repo

to copy all old snapshots. I want to merge the snapshots in such a way that the deduplication works in between repositories. It seems that this requires that the chunker parameters must be the same for the two depositories.

I checked the following for the two repositories:

restic -r repo cat config

and I see that the strings for the chunker_polynomial are not the same (although, this is chunker_polynomial not chunker parameters).

Is there a way that this could be done in Restic?

Rechunking is currently not possible. That would require the copy command to fully reconstruct snapshots which leads to a whole new bunch of problems.

1 Like

I guess the only solution is to mount one of them, and backup the mounted folder (decrypted data) into a new snapshot in the other.

Might take ages I guess, since all snapshots in the mount must be read.