Ruled order, region identity proven first. Office1 vlan update 4 0
dhcp_on=false -> read back False; verified STOPPED BY PROCESS (pgrep -c
dhcpd = 0 on the rack, because MAAS self-report is not evidence -- the
2026-07-20 Temporal incident class); new region vlan update 0 0
dhcp_on=true primary_rack=c3aqh8 -> read back True on fabric-0 / space
metal-admin; verified RUNNING BY PROCESS on hot-kid with the rack
re-checked at 0. Exactly one DHCP server on the segment. All 10 machines
Ready and powered off throughout.

Recorded so it is not later read as a fault: the new region also starts
dhcpd6 where the Office1 rack ran v4 only. Its v6 metal-admin subnet has
NO dynamic range -- only rfc-4291-2.6.1 and assigned-ip/reserved, same as
the old region -- so it has nothing to hand out and nodes keep their ruled
statics.

The permission wall was a rule that FAILED TO MATCH, not a classifier
fault. Existing ask rules pin the double-quote form while the commands used
single quotes, and pin the maas admin profile while the new region needs
maas vr1-dc0-region. Operator-approved ask rules added to
settings.local.json (gitignored; committed team policy unchanged),
profile-agnostic so both regions match, plus read-only pgrep/ps allow
rules. The first rule shape I proposed pinned maas admin and would have
matched step 1 while silently missing step 3 -- stalling the cutover at
exactly the two-servers boundary.

Capture docs/audit/dc0-dhcp-handover-20260730.txt.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HvCyrwvYTTcDYnRErfMsNf