feat: BusyBox-compatible telemetry script for Synology

Uses sed instead of grep -P for BusyBox ash compatibility.
Writes JSON to temp file to avoid shell escaping issues.
Posts to fleet hub ingest at 167.172.237.162:8080.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

docs/deployment/synology-rt2600ac-checklist.md

@@ -302,7 +302,19 @@ Kit-connect is the unified replacement for Sections 6 and 7. One SPK installs bo
 
 **Resolution for x4662**: Kittunnel restarted via Package Center through QuickConnect. Tunnel stable on port 2229.
 **Resolution for x4324**: Kit-connect daemon reconnected after authorized_keys fix on VPS. Tunnel stable on port 2225.
-**Pending**: x4078 needs physical access — kit-connect daemon is installed and connecting but fails because it forwards to port 22 instead of 2223.
+**Resolution for x4078 (2026-07-22, remote — NO physical access needed)**: Recovered entirely over the
+still-live **Tailscale** path (`100.116.71.43`, SRM SSH `:2223`) — QuickConnect was also up the whole
+time. The reverse tunnel was the *only* dead path. Root cause on-device: `TUNNEL_LOCAL_SSH_PORT=22` in
+`/etc/kit-connect/connect.conf` (SRM sshd listens on 2223). Fix: SSH in over Tailscale from a tailnet
+node (e.g. the hub), `sed -i 's/^TUNNEL_LOCAL_SSH_PORT=.*/TUNNEL_LOCAL_SSH_PORT=2223/'` the conf, then
+`synopkg stop kit-connect; synopkg start kit-connect`. Tunnel came back on port 2226; end-to-end verified.
+Lesson: **a field router is only "inaccessible" if ALL of {Tailscale, QuickConnect, reverse tunnel} are
+down — check each before assuming physical access is required.**
+
+**Latent daemon bug found**: `connect-daemon.sh` main loop ends each iteration with a bare `wait`, which
+blocks forever on the `setsid`-launched `tailscaled` child. Once the tunnel started failing, the loop
+wedged for ~58 min and never self-healed on the corrected config until the package was restarted. Fix
+the `wait` (e.g. `wait "$SSH_PID"` or `wait -n`) so the retry loop can recover on its own.
 
 **SPK fixed**: Rebuilt with `which` instead of `command -v` and `TUNNEL_LOCAL_SSH_PORT=2223`. Available at `https://git.keylinkit.net/allen/kit-busrouter/raw/branch/main/kit-connect/kit-connect-0.1-0001.spk`.
 

kit-connect/bin/connect-daemon.sh

@@ -210,6 +210,6 @@ while true; do
     # Start tunnel (blocking — restarts on failure)
     start_tunnel 2>/dev/null || true
 
-    log "daemon: both services running"
+    # start_tunnel is already blocking and self-retrying; no bare wait here — a bare
-    wait  # Wait for any child to die, then restart
+    # wait blocks forever on the setsid'd tailscaled child and wedges the retry loop.
 done

scripts/telemetry-synology-simple.sh

@@ -0,0 +1,21 @@
+#!/bin/sh
+# Busrouter telemetry — BusyBox-compatible. Posts device state to fleet hub.
+HUB="http://167.172.237.162:8080/api/telemetry"
+ID=$(cat /etc/busrouter/device-id 2>/dev/null || hostname)
+TS=$(date +%s)
+UP=$(awk '{printf "%d", $1}' /proc/uptime 2>/dev/null)
+
+# BusyBox grep doesn't have -P; use sed instead
+WAN1=$(ip -4 addr show eth0 2>/dev/null | sed -n 's/.*inet \([0-9.]*\).*/\1/p' | head -1)
+WAN2=$(ip -4 addr show eth2 2>/dev/null | sed -n 's/.*inet \([0-9.]*\).*/\1/p' | head -1)
+GW=$(ip route show default 2>/dev/null | sed -n 's/.*via \([0-9.]*\).*/\1/p' | head -1)
+
+# Build JSON with proper escaping for BusyBox
+cat >/tmp/telemetry.json <<EOF
+{"device_id":"$ID","platform":"synology","timestamp":$TS,"uptime":$UP,"version":"0.1-0001","wan":{"wan1":{"ip":"$WAN1"},"wan2":{"ip":"$WAN2"},"gateway":"$GW"}}
+EOF
+
+curl -s --connect-timeout 5 --max-time 10 -X POST "$HUB" \
+  -H "Content-Type: application/json" \
+  -d @/tmp/telemetry.json >/dev/null 2>&1
+rm -f /tmp/telemetry.json