openclaw - 💡(How to fix) Fix [Bug]: Bonjour plugin: CIAO PROBING CANCELLED unhandled promise rejection crashes gateway on Linux [5 comments, 5 participants]

Bug type

Behavior bug (incorrect output/state without crash)

Beta release blocker

No

Summary

Environment

• OS: Linux 6.8.0 (x64)
• Node: v22.x
• OpenClaw: 2026.4.23 (also confirmed on 2026.4.24 by user)
• Install: npm global (/home/onridges/.npm-global/lib/node_modules/openclaw)
• Platform: Linux VM on ESXi, LAN bind 0.0.0.0:18789

Bug Description

The gateway starts successfully but crashes approximately 12–15 seconds after startup due to an unhandled Promise rejection in the Bonjour/mDNS advertising layer. The process enters a restart loop and never stabilizes.

Steps to Reproduce

1. Start openclaw-gateway.service (or openclaw gateway start)
2. Wait ~12 seconds
3. Observe: Unhandled promise rejection: CIAO PROBING CANCELLED
4. systemd restarts the process → repeat indefinitely

Relevant Log Snippet

Steps to reproduce

Steps to Reproduce

1. Install or upgrade to OpenClaw 2026.4.23 or 2026.4.24 on Linux
2. Start the gateway via systemd: systemctl --user start openclaw-gateway.service
3. Wait 12–15 seconds after startup
4. Observe: gateway process crashes with Unhandled promise rejection: CIAO PROBING CANCELLED
5. systemd automatically restarts → crash loop begins

Expected behavior

upgrade sucessfully

Actual behavior

1. Install or upgrade to OpenClaw 2026.4.23 or 2026.4.24 on Linux
2. Start the gateway via systemd: systemctl --user start openclaw-gateway.service
3. Wait 12–15 seconds after startup
4. Observe: gateway process crashes with Unhandled promise rejection: CIAO PROBING CANCELLED
5. systemd automatically restarts → crash loop begins

OpenClaw version

2026.4.24

Operating system

Ubuntu 24.04 LTS linux

Install method

npm

Model

minimax

Provider / routing chain

openclaw->minimax

Additional provider/model setup details

No response

Logs, screenshots, and evidence

Apr 27 10:53:09 openclaw node[8652]: [plugins] bonjour: watchdog detected non-announced service; attempting re-advertise (gateway fqdn=openclaw._openclaw-gw._tcp.local. host=openclaw.local. port=18789 state=probing)
Apr 27 10:53:22 openclaw node[8652]: [plugins] bonjour: restarting advertiser (service stuck in probing for 12885ms (gateway fqdn=openclaw._openclaw-gw._tcp.local. host=openclaw.local. port=18789 state=probing))
Apr 27 10:53:22 openclaw node[8652]: [plugins] bonjour: advertised gateway fqdn=openclaw._openclaw-gw._tcp.local. host=openclaw.local. port=18789 state=unannounced
Apr 27 10:53:22 openclaw node[8652]: [openclaw] Unhandled promise rejection: CIAO PROBING CANCELLED
Apr 27 10:53:22 openclaw node[8652]: [openclaw] wrote stability bundle: /home/onridges/.openclaw/logs/stability/...
Apr 27 10:53:22 openclaw systemd[1725]: openclaw-gateway.service: Main process exited, code=exited, status=1/FAILURE

Impact and severity

No response

Additional information

Root Cause Analysis

The @homebridge/ciao library (used by the bonjour plugin) fails to advertise the mDNS service — the advertising attempt gets stuck in probing state indefinitely. The watchdog detects this after ~12s, cancels the operation, and the resulting CIAO PROBING CANCELLED rejection is unhandled, crashing the process.

Suggested Fixes (in order of preference)

1. Fix the unhandled rejection in the bonjour plugin's ciao advertising code so CIAO PROBING CANCELLED doesn't crash the gateway
2. Add try/catch around the bonjour advertiser restart logic to prevent unhandled rejection propagation
3. Make bonjour non-critical: wrap the bonjour plugin initialization so a probing failure doesn't terminate the gateway process
4. Add a config option to disable bonjour for users who don't need mDNS discovery

Impact

High — gateway is effectively unusable on Linux systems where ciao/mDNS advertising fails, as the process crashes in a loop.