IT management
Someone to look after the server and keep it running - from a light touch to taking it over.
Servers fail in boring ways: disks fill up, memory runs out, TLS certificates expire, an update breaks something overnight. Most of that is avoidable if someone is watching.
Ahead of the failure
Checklists for the stuff that repeats, and light automation for the rest. Monitoring that warns you before users notice, and backups we have actually restored, so we know they work.
How involved
As light as being on call when you can’t fix something, or taking over the server so you don’t have to think about it.