This really is the way.
It goes beyond documentation too - it allows me to migrate to new hosts or to easily automate upgrading the OS release version.
I have a docusaurus site for my homeland and I have ansible and terraform generate files for the docs so I don’t have to record anything. Some of the stuff I note down:
- DNS leases
- General infra diagrams
- IP info
- Host info
Or on their phone.
Most of the time it’s used to help guests get onto the wifi quickly.
I also find it handy to get the wifi password when on-boarding smart devices or whatever new gadget.