Zero-downtime delivery · 10 / 10 ·
Rollback moves the switch back
Rollback is not a rebuild. The old slot still holds v1.2.3. The playbook patches Caddy back to that port and writes state.json.
- Green is live, but the new version is wrong.
- Caddy returns to blue. The old version is still in state.json.
Drain mode shows old requests finishing before the old slot stops.
- New traffic goes to green. Blue still finishes old requests.
- Old requests finished. Blue is stopped.
If a new release fails the health check, you never reach this step. The health gate already kept readers on the old version.