# Partial rollback leaves inconsistent state: first 30 minutes checklist

Source: https://releasefailures.com/incidents/partial-rollback-leaves-inconsistent-state/
Content version: 1.0.0
Verified on: 2026-10-21
Licence: CC BY 4.0

Definition: Only some services are rolled back and the system runs with incompatible versions.
- [ ] FM-01 List the version each service and server runs right now and mark every one that differs from the intended version.
- [ ] FM-02 If services run mixed versions and keep acting on requests, stop incoming work to the affected cluster.
- [ ] FM-03 Check caches and stores for entries the new version wrote before rolling any code back.
- [ ] FM-04 Decide between a manual downgrade of every service and a roll forward, based on whether the old version can read data the new version wrote.
- [ ] FM-05 Compare the times of new client error alerts with the rollback time before treating them as a separate fault.
- [ ] FM-06 Confirm every service and server reports the same version after the downgrade or roll forward finishes.
- [ ] FM-07 Post a status update that names the affected environment and the degraded features.