Follow in order. The aim is to restore service first and explain second.

First 15 minutes

• [ ] Confirm from a second network that it is really down
• [ ] Open an incident with the time
• [ ] Check in this order: domain expired, DNS, SSL, host status page, server, application

Restore

• [ ] If a recent update caused it, roll back that update first
• [ ] Restore from backup only when rollback fails, and note what data since then is lost

Tell the client

• [ ] Send one short message with what happened, what you did and when it will be back

Afterwards

• [ ] Fill Root cause and fix
• [ ] Add one check to your Monthly care run so this cause gets caught next time