Ha! We used this concept over a decade ago to stop our servers containing credit card information from our customers from being rebooted unexpectedly and unseal

Ha! We used this concept over a decade ago to stop our servers containing credit card information from our customers from being rebooted unexpectedly and unsealing themselves/permitting traffic. What a fun memory, other tricks we employed was to disable the TTY and any form of remote login; and heavily auditing and restricting the information coming in via a WAF. It was very frustrating for them to have a fault because in order to reboot the system (which is basically all you can do): you need the CIO and one of the trusted product managers and one of the trusted sysadmins. The issue with that final one was that the trusted sysadmins could not be the same trusted sysadmins who could access the remote logging infrastructure. — also the CIO was a large bus factor, but I was told the CEO also had that key. If you work on payment systems at Facebook/meta or Oracle Netsuite then likely some of that code still exist there. Maybe someone can confirm.