Prerequisites

Server

• OS: Linux (Debian/Ubuntu recommended)
• Docker and Docker Compose v2
• Public IP (or routable address) for SIP — set HOST_IP in exchange .env
• Host networking for exchange container (default in docker-compose.yaml)

Network

Port	Protocol	Purpose
5060	UDP	SIP from PBX
8080	TCP	HTTP API (/bridges, /stats) — bind localhost if using nginx
62040–64040	UDP	MMDVM local ports per bridge (configurable range)

Firewall SIP to your PBX source IP only.

PBX

• Asterisk / FreePBX with outbound PJSIP or SIP trunk
• Ability to add custom dialplan (IVR + Dial() with pre-dial headers)
• Custom sounds for IVR prompts (optional but recommended)

DMR backend

• A SystemX, MMDVM, or compatible server you are authorised to use
• Credentials (DMR_ADDRESS, DMR_PORT, DMR_PASSWORD in .env)
• Confirm your network allows multiple concurrent MMDVM logins from one public IP if you plan more than one call

Build tools (first-time bridge build)

Building sip-dmr-bridge may require:

• Git with SSH access to sip-usrp-bridge if submodules/private deps apply
• Sufficient disk for Docker layers and build cache (~10 GB+ comfortable)

Secrets

Generate a strong random token for SIP_AUTH_TOKEN. Store on exchange (.env) and configure PBX to send it as X-Auth-Token. Never commit secrets to git.

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Last update: August 17, 2026 21:08:54
Last updated by: MØVUB

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