# Runbook: roll back a change

## Purpose

Restore a known-good state after a change failed verification or caused a
regression.

## Scope

- Applicable: Compose services, DNS records, firewall rules, and Ansible-managed config that have a rollback point.
- Not applicable: destructive migrations without a backup (route to the owning runbook, e.g. `vaultwarden-sqlite-to-postgres.md` §Rollback).

## Ownership

- Owner: personal ops (Windy)
- Last reviewed: 2026-08-17
- Related systems: all production hosts

## Preconditions

- A rollback point exists: backup, prior config, or known-good commit/playbook state.
- The failing change and its symptoms are recorded.

## Safety

- Confirm the rollback target before acting; do not roll back unrelated changes.
- Verify after rollback; a rollback that is not verified is not complete.

## Procedure

### Step 1 — Confirm the target

**Action** — record the change to revert (playbook run, config edit, DNS change) and its intended prior state.

**Expected** — the exact prior state is known and reachable.

**Decision** — prior state known → Step 2; unknown → `STOP` and escalate.

### Step 2 — Revert

**Action** — apply the documented reversal for the change type:

- Compose config: re-apply the prior config and reconcile (or `git revert` the change then reconcile).
- DNS: restore the previous record value on PowerDNS.
- Firewall: re-apply the prior allowlist via the gated playbook.
- General repo change: `git revert <sha>`.

**Expected** — the prior configuration is in place.

**Verification** — re-run the relevant health report / endpoint check and confirm green.

**Rollback** — if the rollback itself fails, `STOP`; keep the original management session open and escalate.

## Final Verification

- Health report green after rollback.
- The incident and rollback are recorded in the Linear `vps` issue.

## References

- [`release.md`](release.md)
- [`ansible-operations.md`](ansible-operations.md)