Tango
A pair of Lenovo ThinkStation PGX compact AI workstations (tango0, tango1), linked
back-to-back with a QSFP cable. One of the two has been out of the rack since August 2026.
At a glance
| Role | AI workstation pair |
| Machines | 2× Lenovo ThinkStation PGX |
| Interconnect | Direct QSFP link, ~118 Gbit/s measured |
| Network | Racked node on 192.168.88.43 (dynamic); .20 / .21 are reserved but unused — see Network |
| Rack | U36, front face — the two compact chassis share one U (see rack layout) |
| Status | One of the two is out of the rack (Aug 2026) |
| Access | VPN, then SSH (when racked) |
Hardware
- 2× Lenovo ThinkStation PGX
Network
When racked, the machines sit on the appliances subnet and are additionally linked to each other by a direct QSFP cable (point-to-point, no switch); each machine has the other defined in /etc/hosts.
| Node | LAN IP | QSFP link IP |
|---|---|---|
tango0 | 192.168.88.20 | 10.12.0.2 |
tango1 | 192.168.88.21 | 10.12.0.3 |
192.168.88.43, not .20 (August 2026)It presents MAC 4C:BB:47:2F:44:25, which has no reservation, so it takes a dynamic address under
the factory host-name spark-4425 — the table above does not apply to it. The .20 / .21
reservations are bound to two other MACs. Either the cabled port is not the intended LAN one, or the
reservations cover a different interface. Open item:
ops todo → tango.
The QSFP link was measured at ~118 Gbit/s aggregate (iperf, 8 parallel streams).
Maintenance notes
- Firmware updates seem to fail when no display is connected — try at your own risk.
Access
See Getting access for details about requesting access.