Establishing what you have.
WHEN TO DO IT
Annually After taking over an environment Before any significant change
WHAT TO RECORD
- Every device: what, where, who
- Addressing: ranges and fixed assignments
- Equipment: model, age, firmware status
- Cabling: runs and what they connect
- Wireless: networks and coverage
Provider details and contracts What is exposed externally
THAT LAST ONE
Frequently more than anyone intended.
WHAT TO CHECK
Whether every connected device is accounted for Whether equipment is still supported Whether documentation matches reality
WHAT YOU WILL FIND
Devices nobody recognises Configuration nobody remembers making Equipment past support Rules and exposures nobody can explain
WHAT TO DO ABOUT EACH
Identify it, then decide deliberately.
WHAT NOT TO DO
Remove things you do not understand without establishing what depends on them.
WHAT TO PRODUCE
Updated documentation.
WHAT THAT ENABLES
Planning, troubleshooting, and handover.
