Bonjour discovery

OpenClaw can use Bonjour (mDNS/DNS-SD) to discover an active gateway (WebSocket endpoint). Multicast local. browsing is a LAN-only convenience: the bundled bonjour plugin owns LAN advertising, auto-starting on macOS hosts and opt-in on Linux, Windows, and containerized gateway deployments. The same beacon can also publish through a configured wide-area DNS-SD domain for cross-network discovery. Discovery is best-effort and does not replace SSH or Tailnet-based connectivity.

Wide-area Bonjour (Unicast DNS-SD) over Tailscale

If the node and gateway are on different networks, multicast mDNS can't cross the boundary. Keep the same discovery UX by switching to unicast DNS-SD ("Wide-Area Bonjour") over Tailscale:

Run a DNS server on the gateway host, reachable over the Tailnet.
Publish DNS-SD records for _openclaw-gw._tcp under a dedicated zone (example: openclaw.internal.).
Configure Tailscale split DNS so your chosen domain resolves via that DNS server for clients, including iOS.

openclaw.internal. above is just an example — OpenClaw supports any discovery domain. iOS/Android nodes browse both local. and your configured wide-area domain.

Gateway config

json5

{
  gateway: { bind: "tailnet" }, // tailnet-only (recommended)
  discovery: { wideArea: { enabled: true, domain: "openclaw.internal" } },
}

discovery.wideArea.domain also accepts the OPENCLAW_WIDE_AREA_DOMAIN env var as a fallback when unset.

One-time DNS server setup (gateway host, macOS only)

bash

openclaw dns setup --apply

This command is macOS-only and requires Homebrew and a running Tailscale connection. It installs CoreDNS (brew install coredns) and configures it to:

listen on port 53 only on the gateway's Tailscale interfaces
serve your chosen domain (example: openclaw.internal.) from ~/.openclaw/dns/<domain>.db

Run without --apply first to preview the plan (domain, zone file path, detected Tailnet IP, recommended config) without installing anything.

Validate from a Tailnet-connected machine:

bash

dns-sd -B _openclaw-gw._tcp openclaw.internal.
dig @<TAILNET_IPV4> -p 53 _openclaw-gw._tcp.openclaw.internal PTR +short

Tailscale DNS settings

In the Tailscale admin console:

Add a nameserver pointing at the gateway's Tailnet IP (UDP/TCP 53).
Add split DNS so your discovery domain uses that nameserver.

Once clients accept Tailnet DNS, iOS nodes and CLI discovery can browse _openclaw-gw._tcp in your discovery domain without multicast.

Gateway listener security

The gateway WS port (default 18789) binds to loopback by default. For LAN/Tailnet access, bind explicitly and keep auth enabled. For Tailnet-only setups, set gateway.bind: "tailnet" in ~/.openclaw/openclaw.json and restart the gateway (or the macOS menubar app).

What advertises

Only the gateway advertises _openclaw-gw._tcp. LAN multicast advertising comes from the bundled bonjour plugin when enabled; wide-area DNS-SD publishing stays gateway-owned.

Service types

_openclaw-gw._tcp - gateway transport beacon, used by macOS/iOS/Android nodes.

TXT keys (non-secret hints)

Key	When present
`role=gateway`	Always.
`displayName=<friendly name>`	Always.
`lanHost=<hostname>.local`	Always.
`gatewayPort=<port>`	Always (gateway WS + HTTP).
`transport=gateway`	Always.
`gatewayTls=1`	Only when TLS is enabled.
`gatewayTlsSha256=<sha256>`	Only when TLS is enabled and a fingerprint is available.
`gatewayDirectReachable=1`	Only when the gateway is directly reachable (not only via a relay/proxy path).
`canvasPort=<port>`	Only when the canvas host is enabled; currently the same as `gatewayPort`.
`tailnetDns=<magicdns>`	mDNS full mode only; optional hint when Tailnet is available.
`sshPort=<port>`	Full mode only; omitted in minimal and off modes.
`cliPath=<path>`	Full mode only; omitted in minimal and off modes.

Security notes:

Bonjour/mDNS TXT records are unauthenticated. Clients must not treat TXT as authoritative routing.
Clients should route using the resolved service endpoint (SRV + A/AAAA). Treat lanHost, tailnetDns, gatewayPort, and gatewayTlsSha256 as hints only.
SSH auto-targeting should likewise use the resolved service host, not TXT-only hints.
TLS pinning must never let an advertised gatewayTlsSha256 override a previously stored pin.
iOS/Android nodes should treat discovery-based direct connects as TLS-only and require explicit user confirmation before trusting a first-time fingerprint.

Debugging on macOS

Built-in tools:

bash

# Browse instances
dns-sd -B _openclaw-gw._tcp local.

# Resolve one instance (replace <instance>)
dns-sd -L "<instance>" _openclaw-gw._tcp local.

If browsing works but resolving fails, you're usually hitting a LAN policy or mDNS resolver issue.

Debugging in Gateway logs

The gateway writes a rolling log file (printed on startup as gateway log file: ...). Look for bonjour: lines, especially:

bonjour: advertise failed ...
bonjour: suppressing ciao cancellation ...
bonjour: ... name conflict resolved / hostname conflict resolved
bonjour: watchdog detected non-announced service ...
bonjour: disabling advertiser after ... failed restarts ...

The watchdog treats active probing, announcing, and fresh conflict-renames as in-progress states. If the service never reaches announced, OpenClaw recreates the advertiser and, after repeated failures, disables Bonjour for that gateway process instead of re-advertising forever.

Bonjour uses the system hostname for the advertised .local host when it's a valid DNS label. If the system hostname contains spaces, underscores, or another invalid DNS-label character, OpenClaw falls back to openclaw.local. Set OPENCLAW_MDNS_HOSTNAME=<name> before starting the gateway when you need an explicit host label.

Debugging on iOS node

The iOS node uses NWBrowser to discover _openclaw-gw._tcp.

To capture logs: Settings -> Gateway -> Advanced -> Discovery Debug Logs, then Settings -> Gateway -> Advanced -> Discovery Logs -> reproduce -> Copy. The log includes browser state transitions and result-set changes.

When to enable Bonjour

Bonjour auto-starts for empty-config gateway startup on macOS hosts, since the local app and nearby iOS/Android nodes commonly rely on same-LAN discovery.

Enable it explicitly when same-LAN auto-discovery is useful on Linux, Windows, or another non-macOS host:

bash

openclaw plugins enable bonjour

When enabled, Bonjour uses discovery.mdns.mode to decide how much TXT metadata to publish; the same mode controls optional TXT hints in wide-area DNS-SD records. Modes:

Mode	Behavior
`minimal` (default)	Core TXT keys only; omits `sshPort`, `cliPath`, `tailnetDns`.
`full`	Adds `sshPort`, `cliPath`, `tailnetDns` — use when clients need those hints.
`off`	Suppresses LAN multicast without changing plugin enablement; wide-area DNS-SD can still publish the minimal beacon when `discovery.wideArea.enabled` is true.

When to disable Bonjour

Leave Bonjour disabled when LAN multicast advertising is unnecessary, unavailable, or harmful — common cases are non-macOS servers, Docker bridge networking, WSL, or a network policy that drops mDNS multicast. The gateway stays reachable through its published URL, SSH, Tailnet, or wide-area DNS-SD; only LAN auto-discovery is unreliable.

Use the env override for deployment-scoped problems (safe for Docker images, service files, launch scripts, one-off debugging — it disappears when the environment does):

bash

OPENCLAW_DISABLE_BONJOUR=1

Use plugin configuration when you intentionally want to turn off the bundled LAN discovery plugin for that OpenClaw config:

bash

openclaw plugins disable bonjour

Docker gotchas

The bundled Bonjour plugin auto-disables LAN multicast advertising in detected containers when OPENCLAW_DISABLE_BONJOUR is unset. Docker bridge networks usually don't forward mDNS multicast (224.0.0.251:5353) between the container and the LAN, so advertising from the container rarely makes discovery work.

Gotchas:

Bonjour auto-starts on macOS hosts and is opt-in elsewhere. Leaving it disabled doesn't stop the gateway — it only skips LAN multicast advertising.
Disabling Bonjour doesn't change gateway.bind; Docker still defaults to OPENCLAW_GATEWAY_BIND=lan so the published host port works.
Disabling Bonjour doesn't disable wide-area DNS-SD. Use wide-area discovery or Tailnet when the gateway and node aren't on the same LAN.
Reusing the same OPENCLAW_CONFIG_DIR outside Docker doesn't persist the container auto-disable policy.
Set OPENCLAW_DISABLE_BONJOUR=0 only for host networking, macvlan, or another network where mDNS multicast is known to pass; set it to 1 to force-disable.

Troubleshooting disabled Bonjour

If a node no longer auto-discovers the gateway after Docker setup:

Confirm whether the gateway is running in auto, forced-on, or forced-off mode:
bash
```
docker compose config | grep OPENCLAW_DISABLE_BONJOUR
```
Confirm the gateway itself is reachable through the published port:
bash
```
curl -fsS http://127.0.0.1:18789/healthz
```
Use a direct target when Bonjour is disabled:
- Control UI or local tools: http://127.0.0.1:18789
- LAN clients: http://<gateway-host>:18789
- Cross-network clients: Tailnet MagicDNS, Tailnet IP, SSH tunnel, or wide-area DNS-SD
If you deliberately enabled the Bonjour plugin in Docker and forced advertising with OPENCLAW_DISABLE_BONJOUR=0, test multicast from the host:
bash
```
dns-sd -B _openclaw-gw._tcp local.
```
If browsing is empty, or Gateway logs show repeated ciao watchdog cancellations, restore OPENCLAW_DISABLE_BONJOUR=1 and use a direct or Tailnet route.

Common failure modes

Bonjour doesn't cross networks: use Tailnet or SSH.
Multicast blocked: some Wi-Fi networks disable mDNS.
Advertiser stuck in probing/announcing: hosts with blocked multicast, container bridges, WSL, or interface churn can leave the ciao advertiser in a non-announced state. OpenClaw retries a few times, then disables Bonjour for the current gateway process instead of restarting the advertiser forever.
Docker bridge networking: Bonjour auto-disables in detected containers. Set OPENCLAW_DISABLE_BONJOUR=0 only for host, macvlan, or another mDNS-capable network.
Sleep/interface churn: macOS may temporarily drop mDNS results; retry.
Browse works but resolve fails: keep machine names simple (avoid emojis or punctuation), then restart the gateway. The service instance name derives from the host name, so overly complex names can confuse some resolvers.

Escaped instance names (`\032`)

Bonjour/DNS-SD often escapes bytes in service instance names as decimal \DDD sequences (spaces become \032). This is normal at the protocol level; UIs should decode for display (iOS uses BonjourEscapes.decode).

Enabling / disabling / configuration

Setting	Effect
`openclaw plugins enable bonjour`	Enables the bundled LAN discovery plugin on hosts where it isn't default-enabled.
`openclaw plugins disable bonjour`	Disables LAN multicast advertising by disabling the bundled plugin.
`OPENCLAW_DISABLE_BONJOUR=1` (or `true`/`yes`/`on`)	Disables LAN multicast advertising without changing plugin config.
`OPENCLAW_DISABLE_BONJOUR=0` (or `false`/`no`/`off`)	Forces LAN multicast advertising on, including inside detected containers.
`discovery.mdns.mode`	`off` \| `minimal` (default) \| `full` — see modes above.
`gateway.bind`	Controls the gateway bind mode in `~/.openclaw/openclaw.json`.
`OPENCLAW_SSH_PORT`	Overrides the SSH port when `sshPort` is advertised (full mode).
`OPENCLAW_TAILNET_DNS`	Publishes a MagicDNS hint in TXT when mDNS full mode is enabled.
`OPENCLAW_CLI_PATH`	Overrides the advertised CLI path (full mode).

macOS hosts auto-start the bundled LAN discovery plugin by default. When the Bonjour plugin is enabled and OPENCLAW_DISABLE_BONJOUR is unset, Bonjour advertises on normal hosts and auto-disables inside detected containers (Docker, Fly.io machines, and common container runtimes).

Discovery policy and transport selection: Discovery
Node pairing + approvals: Gateway pairing

Wide-area Bonjour (Unicast DNS-SD) over Tailscale

Gateway config

One-time DNS server setup (gateway host, macOS only)

Tailscale DNS settings

Gateway listener security

What advertises

Service types

TXT keys (non-secret hints)

Debugging on macOS

Debugging in Gateway logs

Debugging on iOS node

When to enable Bonjour

When to disable Bonjour

Docker gotchas

Troubleshooting disabled Bonjour

Common failure modes

Escaped instance names (\032)

Enabling / disabling / configuration

Related docs

Escaped instance names (`\032`)