The gateway has no IP-passthrough mode, confirmed by the operator with
admin access to it, so the inexpensive path of letting the UDM take the
delegation whole and carve it natively is unavailable at this site.
What remains is a separate DHCPv6 client presenting several identities,
which needs recabling to reach the gateway, splits routing so that one
device handles v4 and another v6, and above all moves IPv6 off the
UDM's zone firewall, leaving the entire policy to be rebuilt elsewhere
before any host could safely hold a globally routable address. The
operator has declined it and the LANs stay without v6.
The index entry also still asserted the superseded single-delegation
conclusion as fact; it now carries the corrected reading alongside the
ruling, so the finding and the decision not to act on it arrive
together rather than the first inviting a retry of the second.
The note concluded AT&T delegates a single /64 and that reading the
address pattern as a /60 was a mistake. A later finding in the same
session overturned that by reading the BGW's own statistics page, and
that correction was never written down; it survived only in the
transcript and surfaced again while assessing whether more prefixes
could be claimed.
The gateway holds the /60 and rations it, keeping half for itself and
delegating the top eight /64s one at a time. Both observations agree:
a prefix-id only carves within a delegation already held, so the
earlier test could not have moved a lone /64 regardless. The limit is
that UniFi solicits once, which makes the requester the ceiling rather
than the carrier.
Durable capture ahead of the ESH fiber install (2026-08-18) that puts the
house behind CGNAT and breaks Site Magic on IPv4 -- IPv6 becomes the
escape hatch and the likely first consumer of fleet v6.
Topology verified rather than assumed: Site Magic between UniFi units,
IPsec IKEv2 colo<->UniFi, and WireGuard as a remote-access convention
only, host-based on ana-wg behind a FortiGate UDP VIP. The FortiGate
port-forwards and never terminates WireGuard, so FortiOS 7.2's lack of
native WG is a non-issue.
IPv6 today: NH3 WAN live, colo and ESH none. AT&T delegates exactly one
/64 at NH3 -- established by forcing the prefix ID from auto to 0 and
observing the subnet not move, since the c110/c11f pattern otherwise
reads as a /60. PD enabled on nh3-iot to measure, then reverted; all
five NH3 LANs are back to ipv6_interface_type=none.
Also fixed on ana-wg: wg0.conf, keys/*_priv, keys/*_psk and the client
configs were mode 644 with private key material in them. Now 600, with
keys/ and configs/ at 700. wg-quick@wg0 stayed active, three peers
intact.
Corrects two stale in-flight rows: the DS regeneration is retired, not
queued, and SPEC-ds-regeneration.md is deleted rather than untracked.
vh