Snapshots and rollback

A snapshot is a fixed repository package set. A channel points to a snapshot; operators move the pointer after checks and promotion. These workflows require a configured snapshot publisher, trusted feed key, and [channel] snapshot_base. Installing pacvamp alone does not provision a distro snapshot service.

Inspect the channel

pacvamp channel
pacvamp channel --offline --json

The report identifies the snapshot, promotion and hold status, reported tests, and whether the mirrorlist is pinned. The offline form uses cached feeds.

A tested label means the package appears in the snapshot's reported test set. Read the suite name and logs: the built-in consistency suite checks repository files and hashes, while a boot or desktop suite exercises a different boundary. A snapshot label does not mean the package itself was exercised. Neither label proves that a package is harmless.

Pin and unpin

Replace SNAPSHOT_ID with an ID from your configured publisher:

pacvamp channel pin SNAPSHOT_ID
pacvamp channel unpin

Pinning verifies the snapshot manifest and promotion, backs up the original /etc/pacman.d/mirrorlist once, and changes the mirrorlist to the fixed snapshot. It does not immediately install or downgrade packages. Unpinning restores the saved mirrorlist; it does not restore earlier installed versions.

Preview a rollback

pacvamp rollback --snapshot SNAPSHOT_ID --dry-run

Review the downgrade plan before running the same command without --dry-run. Execution pins the mirror, refreshes databases, and runs a repository sync with downgrades allowed. By default, the target must have reached rc or stable.

Repository rollback is not a filesystem restore. It does not undo application data migrations, restore all configuration, or roll AUR packages back to prior builds. Pair it with a separately managed filesystem backup/snapshot procedure. Recovery addresses interrupted bookkeeping, not restoration of files.

For publisher formats and promotion rules, see the release-train and snapshot-store specifications. The channel and rollback references list advanced flags.