# Chromebox Runbook > **Box is the main surface.** All operator work goes through Box (box.muse-dev.online). The web UI, `box` CLI, and agents share the same API endpoints. No UI-only powers. Operator's guide to the Chromebox/NetVM browser fleet on `bl` (100.123.153.75). Written 2026-10-04. If you're reading this at 2am, start at [Quick Triage](#quick-triage). ## Quick Triage ```bash # 1. Are the browsers alive? (should return Browser JSON for all 4) for t in 10.201.35.2:9410 10.201.87.2:9420 10.201.202.2:9430 10.201.157.2:9440; do printf "%s: " $t; curl -s -m 5 -o /dev/null -w "%{http_code}\n" http://$t/json/version done # 2. Are the relay processes running? (expect 4 python3 netvm-cdp-relay.py) pgrep -af netvm-cdp-relay | grep -v grep # 3. What did the watchdogs do recently? tail -20 /home/super/Projects/NetVM/chromebox-watchdog.log tail -20 /home/super/Projects/NetVM/cdp-relay-watchdog.log # 4. Are the host veth IPs assigned? (all 4 must show inet 10.201.x.1/30) ip -o addr show | grep '10.201' | grep -v '10.201.202\|10.201.157' # muse+pip ip -o addr show | grep -E '10.201.(35|87|157|202).1/30' ``` If step 1 shows 000 for a node but the browser is fine inside its netns, it's almost certainly a **missing veth IP** or **dead relay** — see [Common Failures](#common-failures). ## Architecture Four nodes, one per agent. 1:1 mapping: node == agent == profile == netns. | Node | Agent | Netns | CDP Port | Veth IP (host) | Peer IP (netns) | Relay Target | |------|-------|-------|----------|----------------|-----------------|--------------| | muse | muse | warp-muse | 9410 | 10.201.35.1/30 | 10.201.35.2 | 10.201.35.2:9410 | | pip | pip | warp-pip | 9420 | 10.201.87.1/30 | 10.201.87.2 | 10.201.87.2:9420 | | 646 | operator-646 | warp-646 | 9430 | 10.201.202.1/30 | 10.201.202.2 | 10.201.202.2:9430 | | opm | opm | warp-opm | 9440 | 10.201.157.1/30 | 10.201.157.2 | 10.201.157.2:9440 | **Traffic path** (per node): ``` host → veth IP:port (e.g. 10.201.87.2:9420) → netvm-cdp-relay.py (runs INSIDE the netns, listens on veth/peer IP) → 127.0.0.1:port (Chromium's DevTools, bound to netns loopback only) → Chromium (headless, Warp egress via WireGuard in the same netns) ``` **Key facts that will save you hours:** - The relay listens on the **veth/peer IP**, NOT on 127.0.0.1. Curling `127.0.0.1:9420` on the host returns nothing — that's normal, not a failure. - Veth IPs are hash-derived via `bin/netvm-names.sh` (`netvm_names ` gives you VETH, GW, PEER_IP). Don't hardcode them in new scripts — source the file. - CDP ports 9410–9440 are registry-pinned. The hash-derived `CDP_PORT` from `netvm-names.sh` is WRONG unless `CDP_PORT_OVERRIDE` was set. Always use the pinned ports above. - Chromium binds DevTools to loopback only. The relay exists because iptables REDIRECT to 127.0.0.1 was proven not to establish — the userspace relay is the reliable path. Don't try to "simplify" it away. ## Watchdogs ### chromebox-watchdog (browser health) - **Script:** `/home/super/Projects/NetVM/bin/chromebox-watchdog.sh` - **Timers:** `chromebox-watchdog-.timer` (one per profile: muse, pip, 646, opm) - **Cadence:** every 2 minutes - **Log:** `/home/super/Projects/NetVM/chromebox-watchdog.log` (10 MB rotation, 1 backup gen) - **Per-profile Chromium output:** `/home/super/Projects/NetVM/chromebox-.log` **Health check stages** (in order, `HEALTH_FAIL_REASON` tells you which broke): 1. Chromium process exists for the profile → else `"no chromium process for profile"` 2. CDP responds on the profile's port → else `"CDP unreachable on :"` 3. Chat page title present in target list → else reason names the missing title **Kill-loop guard** (added 2026-10-04): before killing, checks if a Chromium for the profile launched <2 min ago. If so, skips the kill — it's probably still starting. Prevents the watchdog from murdering a slow-but-working browser. **Relaunch retry** (added 2026-10-04): after relaunch, tries the health check up to 4 times, 15s apart (~60s window). Only declares FAILED if all 4 miss. A single 25s check was too brittle for cold starts (fresh egress IP + Cloudflare handshake can exceed 25s). **What "relaunch FAILED — needs operator attention" means:** the watchdog tried 4 times and the browser still isn't healthy. Check `HEALTH_FAIL_REASON` in the log, then look at the per-profile chromium log. Don't just re-run the watchdog — find out why the browser won't come up. ### cdp-relay-watchdog (relay health) - **Script:** `/home/super/Projects/NetVM/bin/cdp-relay-watchdog.sh` - **Timer:** `cdp-relay-watchdog.timer` - **Service:** `cdp-relay-watchdog.service` (Type=oneshot) - **Cadence:** every 5 minutes - **Log:** `/home/super/Projects/NetVM/cdp-relay-watchdog.log` **Two-stage check** (per node): 1. **Veth IP present** (`veth_healthy`): verifies the host veth interface has its expected IP. If missing → `FAIL_LOUD` in the log, skips relay restart (pointless without the veth). Does NOT auto-recreate the veth — that touches WireGuard/iptables, too invasive for a watchdog. 2. **Relay connectivity** (`relay_healthy`): curls `http://:/json/version` and greps for `"Browser"`. **Never trusts pidfiles** — they go stale and lie. If a relay is down but the veth is fine, the watchdog kills any existing relay for that port and restarts it with the exact `netvm-node-up.sh` invocation (inside the netns, listening on the veth IP). ## The Queue (`cdp_queue.py`) **Why it exists:** nothing coordinated browser operations. DM sends, tab opens, agent reads, and watchdog restarts all hit the same Chromium with zero scheduling. Under fleet concurrency this overwhelms bl's CPU. **Location:** `/home/super/Projects/NetVM/bin/cdp_queue.py` **Design:** - Per-node FIFO queue (muse, pip, 646, opm each independent) - Max **2 concurrent** CDP operations per browser (`MAX_CONCURRENT = 2`) - Priority levels: `PRIORITY_HIGH = 0` (DM sends, user-facing), `PRIORITY_NORMAL = 1` (default), `PRIORITY_LOW = 2` - Cross-process coordination via **flock'd ticket files** in `/tmp/cdp-queue//` (not just threading — `dm.py` shells out to `muse-chat-api.py`, so in-process semaphores alone don't coordinate) - `QueueTimeout` after 60s (configurable per-call) — fails loud, never hangs forever - Warns when wait exceeds 10s **Integration points:** - `muse-chat-api.py`: every CDP session wrapped in `with cdp_slot(node, priority=...)`. Priority from `CDP_PRIORITY` env var (`high`/`normal`/`low`, default `normal`). Graceful fallback: if `cdp_queue` import fails, runs unqueued (nullcontext). This is the single choke point — all current and future callers get queuing. - `dm.py`: `run()` accepts `priority` param, sets `CDP_PRIORITY` in subprocess env. `dm_send()` uses `priority="high"`. Read-back verification stays normal. **Usage:** ```python from cdp_queue import cdp_slot, PRIORITY_HIGH with cdp_slot("opm", priority=PRIORITY_HIGH): # ... CDP operations ... ``` **Monitoring:** `queue_depth(node)` returns current depth. `/tmp/cdp-queue//` has `slot-0.lock` / `slot-1.lock` (persistent, by design) and transient ticket files (should clean up within ~60s of completion — slow async cleanup, not a leak). ## Monitors (side-chat crons) Five runtime crons report to the Chromebox ops side chat. All silent when healthy. | Monitor | Cadence | What it checks | Alert threshold | |---------|---------|----------------|-----------------| | chromebox-watchdog-alerts | 10 min | New `relaunch FAILED` lines in watchdog log | Any new failure | | cdp-relay-health-monitor | 15 min | All 4 relays return HTTP 200 on veth IPs | Any non-200 | | browser-flap-detector | 30 min | `relaunch OK` count per profile in last hour | 3+ restarts/hour | | cdp-latency-monitor | 15 min | CDP `/json/version` response time per node | FAIL or >5s (2–5s tracked, alerts after 3 consecutive) | | chromebox-error-log-watch | 1 hour | FATAL/crash/segfault/OOM in per-profile chrome logs | Any new match | Watermarks live in `~/workspace/goals/chromebox-ops/hidden_files/` so alerts only fire on genuinely new events, not repeats. ## Common Failures and Fixes ### Missing host veth IP **Symptoms:** relay process running, but host can't reach `http://:`. `ip addr show dev ve-` shows no `inet 10.201.x.1/30`. **Cause:** veth pair exists but host-side IP was lost (observed 2026-10-04 for muse/pip — interfaces up, IPs gone). **Fix:** `sudo ip addr add /30 dev ` where GW/VETH come from `netvm-names.sh`. Or run `netvm-node-up.sh ` (idempotent, also fixes anything else that's drifted). **Detect:** cdp-relay-watchdog logs `FAIL_LOUD` for this. Don't just restart the relay — it won't help without the veth IP. ### Stale pidfiles **Symptoms:** `netvm-topology.sh` (old versions) reports relay DOWN when it's up, or UP on the wrong port. `/run/netvm--cdp-relay.pid` points to a dead or recycled PID. **Fix:** fixed 2026-10-04 — topology script now checks by connectivity, not pidfile. If you see pidfile-based checks anywhere else, they're suspect. ### Kill loop (watchdog killing slow browser) **Symptoms:** repeated `unhealthy, relaunching` → `relaunch FAILED` cycles in quick succession. Browser process exists and CDP responds, but the page hasn't loaded yet. **Cause (pre-2026-10-04):** single 25s post-launch check, no retry, no recent-launch guard. **Fix:** fixed 2026-10-04 — 4 retries over 60s + skip kill if launched <2 min ago. If you see this pattern again, the guard may need tuning (longer window). ### Futile-restart loop (agent-health killing a healthy browser) **Symptoms:** `FAIL (api timeout)` + `restarting browser...` + `CRITICAL - still down after restart` repeating every ~10 min for one node while its CDP port stays up (observed 2026-10-06: def, 57 restarts, 155 API FAILs). The API/account layer is broken; restarts cannot fix it, they just murder a working browser. **Fix:** `agent-health.sh` circuit breaker — after 3 consecutive futile restarts the circuit OPENS (alert in log + journal, no more kills) until a 30-min half-open probe or any successful check. Manual reset: `rm /tmp/agent-health-state/circuit- /tmp/agent-health-state/futile-`. Then fix the actual API-layer failure (account session/auth/chat-state), not the browser. ### Setup-fed supervision (new nodes automatically watched) **Wiring:** `netvm-node-up.sh` ends with `ensure-node-supervision.sh ` (idempotent): appends the NODES.md registry row (port from netvm-names pinning, honors CDP_PORT_OVERRIDE) and installs/enables `chromebox-watchdog-.timer`. Provision/onboarding reach it transitively via node-up. Registry-driven supervisors (relay watchdog, agent-health, relay-health/cdp-latency checks) pick up new rows on their next run — no per-node code edits. Heal drift anytime: `sudo bin/ensure-node-supervision.sh --all`. ### Relay on wrong IP **Symptoms:** relay process exists but on the wrong veth IP (e.g., muse's relay on pip's `10.201.87.2` instead of muse's `10.201.35.2`). Port responds on the wrong node's IP. **Cause:** relay started with wrong PEER_IP argument. **Fix:** kill it, restart with the correct IP from `netvm-names.sh`: `sudo ip netns exec warp- setsid nohup python3 bin/netvm-cdp-relay.py 127.0.0.1 ` ### Queue module missing **Symptoms:** everything works but nothing is actually queued — `/tmp/cdp-queue/` never gets ticket files. No errors (graceful fallback hides it). **Cause:** `bin/cdp_queue.py` not present on bl (observed 2026-10-04 — integration was wired but the module file was missing). **Fix:** ensure the file exists and `python3 -m py_compile` passes. It's committed in the NetVM repo — check `git status` if it's gone. ### Orphan relays on random ports **Symptoms:** `pgrep -af netvm-cdp-relay` shows relays on ports like 9269, 9278, 9353, 10239, 10355 (hash-derived, not registry ports). **Cause:** old node-ups or queue tests. Harmless but confusing. **Fix:** kill them. Only 9410/9420/9430/9440 should be running. ## Fleet Status From Blind Shells `box fleet status` probes live (pgrep + peer-IP CDP). Sandboxed shells (own PID/net namespaces, no sudo, no route to 10.201.x.x) fail both probes for every node. Instead of misreporting STOPPED, fleet status falls back to host watchdog evidence (`bin/host_evidence.py`): - Recent watchdog timer runs (journal) with no newer failure line in `cdp-relay-watchdog.log` / `chromebox-watchdog.log` (both are silent-when-healthy) prove the node is up → `ACTIVE [*]`. - `UNKNOWN` means neither live probes nor host evidence could decide (e.g. def/dev have no relay-monitor coverage). - Host evidence never overrides a live local signal, so a fresh outage observed on the host always wins over a minutes-old watchdog run. Same rule drives `box approvals check`: `BLIND` = CDP ok on host, this shell cannot reach it; approval queues are unverified, not clear. ## Key Reference **Node bring-up:** `sudo /home/super/Projects/NetVM/bin/netvm-node-up.sh ` (idempotent — safe to re-run, recreates veth/WireGuard/relay as needed) **Node teardown:** `bin/netvm-node-down.sh ` **Topology check:** `bin/netvm-topology.sh` (connectivity-based since 2026-10-04) **Names:** `bin/netvm-names.sh` — source it: `. bin/netvm-names.sh && netvm_names ` gives you `$NETNS $WG $VETH $VPEER $SUB $GW $PEER_IP` **DM send:** `python3 bin/dm.py send --agent --to --target main "message"` **Commit identity** (shared repo — always use per-command flags, never repo config): ```bash git -c user.name="operator-main" -c user.email="operator-main@frontdoor.local" commit ... ``` **What NOT to do:** - Don't trust pidfiles for relay health — they lie. - Don't curl `127.0.0.1:` on the host to check relays — nothing listens there. - Don't kill a browser that just launched — check `ps -o lstart` first. - Don't commit other sessions' uncommitted work — use `git add -p` or selective staging. - Don't restart browsers to fix relay problems — relays and browsers are independent.