Include timestamp in name of automatic snapshot

[Schroedingers-Cat]

When triggering a snapshot via sudo dnf upgrade, the resulting snapshot name will be root.pre-update. A useful addtion to the snapshot's name would be a timestamp like root.2026-04-05_00-30.pre-update so multiple snapshots can be sorted by creation date when listed. This will make it easier for users to handle multiple snapshots if the snapshot list grows.

[rocketman-code]

Named snapshots already work: atomic-rollback snapshot create tuesday, then rollback tuesday. The default root.pre-update is just what the dnf plugin uses. The help text doesn't make this workflow obvious, which is on me.

Is the need to be able to go back to a specific point in time, or is it specifically the automatic pre-update snapshots that should be individually targetable?

[Schroedingers-Cat]

True, I can name snapshots manually using atomic-rollback snapshot create mysnapshotname. I wondered specifically about the automatic pre-update snapshots having non-colliding names that automatically sort chronologically (e.g. YYYY-MM-DD_HH:MM included in the name).

[rocketman-code]

Shipped in v0.4.0. Automatic snapshots now use the format %Y-%m-%d_%H-%M-%S, one per RPM transaction, so the history accumulates instead of overwriting root.pre-update. Retention keeps the most recent MAX_SNAPSHOTS (default 50, configurable in /etc/atomic-rollback.conf). User-named snapshots are never evicted.

Existing 0.3.x systems have their root.pre-update renamed to its creation timestamp on upgrade, so it joins the rolling history.

sudo dnf update atomic-rollback