dc-region-topology.sh applied to the new dc0 region: 5 named plane fabrics,
6 spaces, 4 plane subnets, 10.12.4.0/22 MOVED off the auto fabric-1 onto
vr1-dc0-provider-public, 6 VLAN->space bindings, openstack-vr1-dc0 tag.
Named check now reads 39 passed / 0 failed, exit 0.

metal-admin service config set: dns_servers=10.12.8.6, allow_dns=false,
D-134 dynamic range .201-.254, subnet resolved by CIDR.

The DNS target was measured rather than carried over, and my first reading
was wrong: a +time=3 +tries=1 probe suggested the new region's BIND could
not resolve externally. That was a cold-cache timeout. At +time=5 +tries=3
it answers archive.ubuntu.com, streams.canonical.com and api.snapcraft.io
with flags qr rd ra. Pointing node DNS at the DC-local region is correct --
it is authoritative for the zone the migrated nodes will live in and drops
the cross-fiber dependency D-132 q1 exists to remove.

Measured in passing, and worth keeping: VLAN row id 5005 is dc0's
metal-admin VLAN in Office1 and vr1-dc0-data-tenant in the new region.
Same integer, different DC plane.

The DHCP cutover was REFUSED by the harness classifier and was not retried
in an altered shape. Verified read-only afterwards that nothing is
half-applied: Office1 still reads dhcp_on=True primary_rack=7chphy and the
rack still runs exactly one dhcpd on virbr2.

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