Types of documentation
A useful set includes physical topology, logical topology, IP and VLAN schedules, device inventory, rack layouts, port maps and key dependencies such as DHCP, DNS, authentication and firewall boundaries.
Physical diagrams
Show switches, firewalls, routers, APs, servers, patch panels and major links. Include useful port identifiers and link speeds where they matter.
Logical diagrams
Show VLANs, subnets, routing boundaries, security zones and major traffic flows without unnecessary physical detail.
Operational records
| Record | Useful fields |
|---|---|
| IP schedule | Subnet, gateway, DHCP range, reservations and purpose. |
| VLAN schedule | VLAN ID, name, subnet and security purpose. |
| Port map | Switch, port, endpoint, VLAN and speed. |
| Cable schedule | Origin, destination, patch ports, media and identifier. |
| Device inventory | Hostname, model, management address, role and location. |
Standards
Use consistent device names, VLAN names, interface descriptions and diagram symbols. Keep documentation versioned and record an owner and review date. Where possible, derive records from authoritative sources such as switch configuration and LLDP/CDP.
Checklist
- Document physical topology.
- Document Layer 3 boundaries.
- Maintain VLAN and IP schedules.
- Maintain port and cable maps.
- Record management and monitoring dependencies.
- Record important firmware versions.
- Version changes and identify the owner.
- Review documentation after significant changes.
Related tools
Generate topology diagrams and use neighbour discovery data as a source for documentation.