The substrate roots pin six MACs per node and the module attaches them in
list order, so macs[i] is enp<i+1>s0. Verified end to end on
vr1-dc0-control-01 against the live carve: enp1s0 metal-admin (PXE),
enp2s0 provider-public (br-ex parent), enp3s0 metal-internal, enp4s0
data-tenant, enp5s0 storage, enp6s0 replication.

This is NOT lib-net.sh's PLANE_CIDRS order, which starts with
provider-public. Anything walking PLANE_CIDRS positionally to place NICs
swaps enp1s0 and enp2s0 and puts the PXE leg on provider-public, stranding
commissioning on a plane with no DHCP. The node carve has no repo tool yet,
so this ordering was about to be re-derived by hand; recording it measured,
with a guard that the two orders differ, is the cheap half of that tool.

dc-selector 88 checks; the trap guard proven able to fail.

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