You could probably install a handler for the event that’s triggered when the power button is pressed. Most OSes do that and pop up a graceful shutdown options window. Most hardware will have a hard shutdown option when you hold the power button for a few seconds. You would probably have to overwrite the BIOS or something at that level to prevent that way out.
alt+sysrq+b bypasses this handler, also switching to another vt should just drop you in a normal shell it as well as long the login shell isn’t modified. There are a lot of ways that can be used to break out.
You could probably install a handler for the event that’s triggered when the power button is pressed. Most OSes do that and pop up a graceful shutdown options window. Most hardware will have a hard shutdown option when you hold the power button for a few seconds. You would probably have to overwrite the BIOS or something at that level to prevent that way out.
You could also just unplug it.
alt+sysrq+b bypasses this handler, also switching to another vt should just drop you in a normal shell it as well as long the login shell isn’t modified. There are a lot of ways that can be used to break out.