The acceptance packet for a just-commissioned Data Domain needs a definitive management-network page, but three email threads quote conflicting IP addresses, gateway, DNS servers, NTP source, and SNMP or mail targets, and nobody can say which values are actually configured. What should the handover documentation be built from?

Commissioning frequently drifts from planning sheets: values get adjusted during bring-up to fit switch ports, VLANs, or available ranges, and those edits are authoritative precisely because they are what the box is running. The as-built practice is therefore to read the final network configuration from the appliance itself and record, in one document, the management addressing, gateway, name servers, time source, and the destination addresses for SNMP and mail, giving operations a single trustworthy baseline for troubleshooting and change management. The design spreadsheet records intent rather than reality; treating it as truth hides drift instead of resolving it, and drift discovered later destroys confidence in every other page of the packet. IPAM is good hygiene but is only as current as its last update, so it can corroborate the as-built yet cannot arbitrate a conflict where email claims disagree. Verbal confirmation from whichever engineer last touched the system is neither reproducible nor auditable and reopens the same dispute at the first incident. Exam caveat: after writing the as-built, update IPAM and DNS to match it so downstream systems converge. Operational check: verify each recorded value from the appliance and then test that the recorded services actually work, resolution, clock sync, SNMP trap, and mail delivery.