Keeping a system current

Keeping a Peios system current is two commands in sequence — refresh to learn what is available, then upgrade to move to it. The other two commands here, downgrade and undo, go the other way: they walk a change back when an upgrade turns out badly.

Refreshing repository metadata #

peipkg refresh [repository]...

peipkg plans against a local, verified copy of each repository's metadata. That copy does not update itself. peipkg refresh is what updates it: for every configured repository — or just the ones you name — peipkg fetches the current signed descriptor and index, verifies them, and replaces the cached copy.

$ peipkg refresh
refreshed "official"
refreshed "internal"

Refresh has two properties worth knowing:

• Repositories are independent. If one repository is unreachable or fails verification, peipkg reports it and carries on with the rest. One bad repository never blocks a refresh of the others.
• A failed refresh changes nothing. If a repository cannot be refreshed, peipkg keeps the metadata it already had. It never falls back to unverified or stale-but-unchecked content. The worst a failed refresh does is leave you on yesterday's view.

What "verified" means here — signing keys, freshness floors, the handling of an unsigned repository — is the subject of Repositories and trust.

Run refresh before an upgrade. An upgrade plans against whatever metadata is cached, so an upgrade without a recent refresh simply moves you to the newest version peipkg last heard about.

Upgrading #

peipkg upgrade [package]...

With no arguments, upgrade considers every installed package and moves each one that has a newer available version forward to it. With one or more package names, it upgrades only those — and still pulls in any new dependencies they need.

$ peipkg refresh && peipkg upgrade
the following changes will be made:
  upgrade    zlib 1.3.1 -> 1.3.2
  upgrade    nginx 1.27.4 -> 1.27.5
proceed? [y/N]

upgrade uses the same plan-and-confirm flow as install — peipkg shows the full set of changes and waits for approval — and the same options:

If there is nothing to do — every package already at its newest version — peipkg says so and exits.

Downgrading #

peipkg downgrade <package> <version>

downgrade moves one package to a specific older version. You name the package and the exact version you want:

$ peipkg downgrade nginx 1.27.4

Older versions are not in a repository's active index — that index lists current versions only. They live in its archive index, which peipkg fetches on demand when you ask for a version that is not current. The package must still exist in some configured repository's archive for the downgrade to be possible.

A downgrade is treated as a deliberate move. Going backward — onto a version that may have known issues a newer one fixed — is one of the actions peipkg flags for explicit authorisation: beyond the routine proceed? prompt, peipkg asks you to authorise the specific downgrade, and --yes does not stand in for that answer. See Elevated authorisation for the full set of actions that work this way.

downgrade accepts --dry-run and --yes, -y with the same meaning as elsewhere.

Undoing the last change #

peipkg undo

undo reverses the most recent committed transaction. If that transaction installed a package, undo removes it; if it upgraded, downgraded, or removed packages, undo restores each one to the version it had before.

$ peipkg undo
undoing transaction 47 (upgrade nginx, zlib)
the following changes will be made:
  downgrade  nginx 1.27.5 -> 1.27.4
  downgrade  zlib 1.3.2 -> 1.3.1
proceed? [y/N]

It is worth being precise about what undo is. It is not a rollback of committed state — the previous transaction really did happen and stays in the history. undo computes the inverse of that transaction and applies it as a brand-new transaction of its own. The history grows; it does not rewind. That new transaction can itself be undone, and so on.

Because restoring an older version is a backward move, undo carries the same explicit-authorisation requirement as downgrade for any package it walks back. It accepts --dry-run and --yes, -y.

To undo something other than the most recent transaction, or to see the history undo works against, use peipkg history — and revert a specific package directly with downgrade.

The routine cycle #

For day-to-day maintenance the loop is:

$ peipkg refresh        # learn what is available
$ peipkg upgrade --dry-run   # preview the move
$ peipkg upgrade        # apply it

downgrade and undo are the recovery moves — reach for them when a refreshed-and-upgraded system has picked up a change you want gone. Every one of these commands is a transaction, so every one of them is atomic and itself reversible.