# LG TV Bridge — Decisions

Format: `YYYY-MM-DD: <decision> — <why>`

- **2026-06-01: Single bridge, single host — runs on steel141, pve173 retired.**
  The bridge had been running on pve173 (always-on node) since 2026-03-23,
  SSHing to steel141 for every TV op. Consolidated everything onto steel141.
  *Why:* the WebOS pairing key (`/home/seth/.aiopylgtv.sqlite`) lives only on
  steel141, so `power_off` always routes through it regardless of bridge host —
  pve173 added an SSH hop and a second host for no real availability gain (the
  TV is uncontrollable whenever steel141 is down anyway). One host, no SSH hop.

- **2026-06-01: Cached-IP discovery, sweep only on miss.** Persist last-known TV
  IP in `~/.cache/lgtv/last_ip`; probe it directly (TCP :3000/:3001). Full /24
  ping-sweep runs only on a cache miss, then re-caches. *Why:* the old code
  ping-swept all 254 hosts over SSH on every 30s HA state poll — slow, network
  spam, and racy (stale ARP) → the chronic "flaky state in HA" symptom.

- **2026-06-01: Robust WoL — unicast + broadcast, ports 9/7, 3 bursts.** *Why:*
  old code sent broadcast-only on ports 9/1235 once. Unreliable wakes. NOTE: the
  remaining wake failures are TV-side (Quick Start+ / Mobile TV On must be ON;
  wired Ethernet far more reliable than Wi-Fi for LG WoL) — not fixable in code.

- **2026-06-01: Deps via `pip --user --break-system-packages` for `seth`.** paho
  + bscpylgtv live in `/home/seth/.local` (PEP 668 box). Matches how bscpylgtv
  was already installed; the systemd unit runs `User=seth`.

## Deferred / Rejected
- **DHCP reservation for the TV (static IP):** not done — Pi-hole doesn't run
  DHCP (router does), so it's Seth's action on the router. The cached-IP probe
  makes it unnecessary for correctness; a reservation would just let us drop the
  sweep-fallback entirely. Add if convenient.
- **Unique per-instance MQTT client_id:** rejected — keeping a fixed
  `lgtv-bridge` id means a duplicate instance is *loud* (reconnect war in broker
  logs) rather than silent. Single-instance discipline is the real guard. (A
  duplicate on 2026-06-01 during this very migration is what surfaced all this.)