60 GHz Wireless

60 GHz links are the metro's tactical backup paths — cheap, fast to deploy, but weather-sensitive. They carry an OSPF cost of 500 so any all-fibre path always wins (routing), and every 60 GHz adjacency runs BFD because the radios hold Ethernet carrier up even when the RF path is dead.

Products

Product	Model	Bands	Failover
Wireless Wire	RBwAPG-60ad / nRAY	60 GHz 802.11ad only	None — drops in rain
Wireless Wire Cube Pro	CubeG-5ac60ad	60 GHz + 5 GHz 802.11ac	Automatic (active-backup bond)

60 GHz is V-band (57–66 GHz), attenuated by rain and foliage. Prefer the Cube Pro on any link that is a sole backup.

Venue dish-backup uplinks run BFD off

The BFD-everywhere rule above is for the OSPF metro backbone. A 60 GHz dish used as a venue-CE eBGP backup uplink is the opposite case: BFD is switched off (bfd_enabled=false on the uplink port, and on the PE's venue-handoff port). The Ethernet carrier stays UP through RF fades, so aggressive BFD would flap on brief fades and can't see a real outage anyway — instead the eBGP session's timers are tightened to hold 9s / keepalive 3s so an outage is still caught in seconds. See venue-ce.

MTU is the critical constraint

The MPLS/VPLS overlay needs L2MTU ≥ 1600 on every hop (MTU policy) — the radios are the bottleneck.

• Set with /interface w60g set wlan60-1 l2mtu=<n> then read it back — hardware silently caps the value.
• Cube Pro: match L2MTU on the 60 GHz interface, the 5 GHz interface and the bridge, or a failover changes the path MTU and blackholes VPLS (the bridge usable MTU is the minimum of its members; 5 GHz maxes ~2290, so 60 GHz is the limit).
• A hop that cannot do 1596/1600 is plain-IP backup only — exclude it from VPLS, or drop PPPoE MTU to 1492.
• Record the verified max L2MTU per link in the registry, and validate with ping <far> size=1580 do-not-fragment.

Pairing & failover (Cube Pro)

Pairing uses /interface w60g station with remote-address = the peer's wlan60-1 MAC (both ends mode=bridge) — not connect-list. Failover is an active-backup bond of the 60 GHz station (primary) and the 5 GHz interface (standby, installation=outdoor). The link is transparent L2; frequencies are 58320 / 60480 / 62640 / 64800; radios manage on 10.253.232.x/29. The only change from factory config is the jumbo MTU.

Recovery

• Reset-button timing by LED: flash (~5 s) = config reset; solid (~10 s) = Etherboot/netinstall.
• Remote recovery only works if pre-armed: boot-device= try-ethernet-once-then-nand plus a remotely power-cyclable PoE port. Reset loses the w60g pairing, so keep the pairing params (SSID, frequency, peer MAC) in the config backup.
• Roof kit may not reach RADIUS over a backup path — an emergency local credential lives in the vault (not reproduced here).

Radio inventory (as-built)

Verified vendor/failover status is incomplete — this is a field-walk TODO. Credentials for these radios live in gitignored discovery/credentials.md.

Link	Radio	Failover
Colo (LEVEL-01) ↔ Old Bank roof	nRAY 60 GHz	None
Colo roof (LEVEL-03) ↔ Charlotte roof	60 GHz TBC	TBC
LEVEL-03 ↔ Irish House	60 GHz TBC	TBC
LEVEL-03 ↔ Old Bank roof (2nd)	60 GHz TBC	TBC (diverse, lands CR-COLOROOF-01)
Old Bank ↔ Castle St hotel	vendor TBC (maybe not MikroTik)	TBC
Charlotte roof ↔ undocumented roof	LHGG-60ad	None
Charlotte roof ↔ Irish House (2nd)	60 GHz TBC	TBC (Irish House dual-homed)
Temple Court ↔ Shiraz 2 / Cumberland	60 GHz TBC	TBC (ISP POP circuits)
Boston (Holmes) ↔ Moloko	60 GHz TBC	TBC (Moloko re-homes to Seel → radio spare)
Boston (Holmes) ↔ Seel St	60 GHz OFFLINE	⭐ dormant ring-closure link — revive

Open items

• Investigate the offline Holmes ↔ Seel dish pair before ordering new hardware for ring closure.
• Confirm the Temple Court → Charlotte roof link (expected in design, not seen in discovery).
• Confirm the vendor of Old Bank ↔ Castle St (recovery differs if it is Ubiquiti).
• Untangle the undocumented Temple Tavern / Reiss static-route roof segment (10.246.100.0/29).
• Pre-arm every roof radio for remote netinstall.