Certificate auto-renewal failed silently on appliance

Scenario

An appliance certificate expires even though auto-renewal was supposedly enabled.

Recommended Resolution Path

1. Inspect the renewal client logs and confirm outbound reachability to the ACME provider.
2. Check whether DNS records, HTTP challenges, or reverse proxy changes broke validation.
3. Validate renewal permissions on the private key and certificate store.
4. Schedule alerting on certificate age rather than trusting renewal alone.

Technician Notes

Confirm the business impact, document the root cause, and capture any preventative follow-up in the PSA or client knowledge base.