Backup subset of filesystem repo to Amazon S3

I am doing a local filesystem backup with Kopia. However, I would like to backup a subset of this (only 3 out of 10 snapshots) to Amazon S3 Glacier Storage. What would probably be the best option here?

I would rule out sync-to as it would only sync the whole backup, right?

What about running a second instance of Kopia for the S3 backup?

(Bonus question: If I wanted to have a copy of the full filesystem backup on another disk… how would I do that? Use sync-to or use another Kopia instance?)

As per docs:

Kopia does not currently support cloud storage that provides delayed access to your files – namely, archive storage such as Amazon Glacier Deep Archive. Do not try it; things will break.

If you are looking for FOSS solution then I would recommend to try rustic. It works with cold storage out of the box.

You can:

  1. simply copy all repo to another location using for example rsync.
  2. copy using sync-to
  3. run another kopia instance

IMO the best option is 3 as in case of 1 and 2 you risk that if your source repo is corrupted you will propagate this corruption to your second copy.