GA-R5: question as presented and the operator's exact utterance are both quoted
in the Status block, dated, and pushed BEFORE any dependent work.

Operator utterance: "Add an OSD volume to node-vm (Recommended)".

Recorded as a D-121 AMENDMENT rather than a new D-number. D-121 is the decision
that ratifies modules/node-vm sizing/count, and its own capacity re-validation
already records "Ceph disk re-run for 4 storage/DC = PASS 5.31 TiB" -- the second
disk was BUDGETED and never BUILT. GA-R3: architectural consequence, but it
amends a ruled node layout rather than establishing new ground.

TWO SCOPE CORRECTIONS landed with the ruling, both of which narrow it:
- It is EIGHT volumes, not eighteen. ceph-osd is placed on the four storage
  nodes per DC (bundle.yaml:556-557, to: ["5","6","7","8"]). The other five
  nodes per DC neither run ceph-osd nor need a second device. My earlier framing
  said "all 18 nodes" -- true of the measured defect, wrong about the fix.
- Rack headroom measured before asserting feasibility: dc0 2.0T available, dc1
  2.9T available under /var/lib/libvirt, thin-provisioned qcow2.

Why (a) over (b): MINIMIZE DELTA TO ROOSEVELT -- Roosevelt storage nodes have
real dedicated disks. Option (b) was also not safe to pick as presented: whether
ceph-osd at the pinned squid/stable supports a directory- or partition-backed
OSD was explicitly UNRESEARCHED, and the audit refused to assert it either way.

THE APPLY IS NOT AUTHORISED BY THIS RULING. Four preconditions recorded, the
sharpest being that re-commissioning is required for MAAS to see the new device,
and whether that preserves the D-134 statics and pinned MACs is UNVERIFIED --
the 2026-07-20 MAC-regeneration incident is the precedent for exactly that class.
modules/node-vm is shared by both DCs, so the change must be additive/opt-in or
it plans against all 18 domains.

Revert: git revert this commit; the amendment is additive and no artifact changed.

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