Backup: Add --stats to borgbackup create options

I'd like more comforting numbers in our own backup monitoring.

Refs privatestorageops#429.

morph/lib/borgbackup.nix

@@ -56,6 +56,9 @@ in {
           BORG_RSH = "ssh -i /run/keys/borgbackup/ssh-key -o StrictHostKeyChecking=accept-new";
         };
 
+	# Output statistics after uploading a backup set
+	extraCreateArgs = "--stats";
+
         # Ciphertext doesn't compress well
         compression = "none";
 

[Jean-Paul Calderone]

"Create" sounds like something that happens around once per system. The configuration.nix man page doesn't help me build any better of an understanding (it just tells me these are arguments to "borg create").

https://borgbackup.readthedocs.io/en/stable/quickstart.html suggests that actually "borg init" is the approximately once-per-system operation and "borg create" then runs many times ... so I guess this is fine?

It might be worth adding a few more words to this part of the config to shorten the path to this discovery for anyone unfamiliar with borg commands though.

[Florian Sesser]

https://borgbackup.readthedocs.io/en/stable/quickstart.html suggests that actually "borg init" is the approximately once-per-system operation and "borg create" then runs many times ... so I guess this is fine?

Correct. I amended the comment, hope it is more useful now.