# Container image base change: first 30 minutes checklist

Source: https://releasefailures.com/incidents/container-image-base-change/
Content version: 1.0.0
Verified on: 2026-10-22
Licence: CC BY 4.0

Definition: A base image update changes libraries or users and the service fails to start.
- [ ] FM-01 Group failing jobs by image tag and digest to confirm the failures follow one image version.
- [ ] FM-02 Compare the base layer of the failing image with the last working image, including distribution release, packet filter backend and user accounts.
- [ ] FM-03 Tell affected users to pin jobs to the last working image tag as the immediate workaround.
- [ ] FM-04 If the image is built in-house, roll the shared tag back to the previous image digest.
- [ ] FM-05 If the image comes from upstream, report the fault to its maintainers with the host details that trigger the failure.
- [ ] FM-06 Post a status update that names the affected image tags and the pin workaround.
- [ ] FM-07 Remove the pin only after the fixed upstream or rebuilt image passes a job on the hosted runners.