Files
video-setup/docs/cli/discovery_cli.md
mikael-lovqvists-claude-agent f3a6be0701 docs: update discovery behaviour — targeted unicast replies, not multicast
Document that immediate re-announcements go directly to the triggering peer
(unicast) rather than to the multicast group, and explain the two conditions
that trigger a reply: new peer and restarted peer (site_id change).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
2026-03-30 04:35:28 +00:00

1.4 KiB

discovery_cli

A development tool for testing the discovery layer. Announces a node on the local network via UDP multicast and prints peers as they appear and disappear.


Build

From the repository root:

make cli

The binary is placed in build/cli/.


Usage

discovery_cli <name> <tcp_port> [flags]
Argument Description
name Node name in namespace:instance form, e.g. v4l2:microscope
tcp_port The TCP port this node listens on for transport connections
flags Comma-separated role list: source, relay, sink, controller (default: source)

Example — announce a source node and watch for peers:

./discovery_cli camera:0 8000 source

Example output as peers are found and lost:

found: unnamed:0  192.168.1.42:8001  site=0  flags=source
found: display:0  192.168.1.55:8002  site=0  flags=sink
lost:  unnamed:0  192.168.1.42:8001

Run two instances on the same machine (different ports) to verify mutual discovery.


Relationship to the Video Routing System

discovery_cli exercises the discovery module, which the video node uses to find peers on the LAN without configuration. The node starts a discovery listener on startup; controllers use discovered peer tables to locate nodes before connecting.

See also: query_cli.md for a combined discovery + protocol query.