Borg server and client compatibility

[oixdbb]

Will a server using borg 1.2 be able to handle borg clients using 1.1 repos?

[ThomasWaldmann]

Yes, just read the hints in the changelog.

[mauromol]

@ThomasWaldmann can you please clarify whether the upgrade notes described in documentation (https://borgbackup.readthedocs.io/en/stable/changes.html#upgrade-notes), when they are generically talking about "upgrading borg", are meant to be understood as "upgrading borg client" or rather server?

I mean. I currently have a bog 1.1.15 client writing to a server which was originally using borg 1.1.x itself. With time, the server was upgraded up to 1.2.6, and now I have a proposed upgrade to 1.4.x. (not yet done, though).
I never followed any upgrade guide on this repo, yet, I never had any problems creating, pruning and checking backups (*always" with the same 1.1.15 client). So, I was now wondering myself if I should start to follow some "upgrade guides" or if I should do that only whenever I will upgrade the client version.

Thank you!

[ThomasWaldmann]

Borg does most stuff client-side and we try to keep the server-side code compatible to older clients (as far as borg 1.x is concerned).

So I think a borg 1.4.0 server should work with borg 1.1.x clients.

Due to the CVE listed at top of the changelog, one must not mix borg client versions when they access the same repo(s) crossing the 1.2.4/1.2.5 version boundary. Either have all clients < 1.2.5 or have all clients >= 1.2.5 (and follow the upgrade notes).