alexeyparshin/xmq repository overview

⁠XMQ

A fast, free MQTT server for Linux and Windows, written in C++.

docker run --rm -p 1883:1883 -p 18883:18883 alexeyparshin/xmq

MQTT is on localhost:1883 and takes clients with no credentials, so there is nothing to set up before the first publish. The configuration interface is on https://localhost:18883 — first sign-in admin / admin, change it right away, and set XMQ_ALLOW_ANONYMOUS=false before the container is reachable from anywhere you do not control.

⁠Settings

Ports: 1883 MQTT, 8883 MQTT over TLS, 18883 web interface.

Mount /etc/xmq to keep the configuration, accounts and certificate across restarts. Raise the descriptor limit for real load: --ulimit nofile=1048576:1048576 — the Docker default of 1024 caps the broker at about a thousand connections.

⁠With persistence

services:
  xmq:
    image: alexeyparshin/xmq
    ports: ["1883:1883", "18883:18883"]
    environment:
      XMQ_PERSISTENCE: "true"
    volumes: ["xmq-config:/etc/xmq"]
    ulimits:
      nofile: {soft: 1048576, hard: 1048576}
    depends_on: [redis_server]
  redis_server:
    image: redis:8-alpine
    command: ["redis-server", "--appendonly", "yes"]
volumes:
  xmq-config:

⁠Logs and tools

The log goes to stdout, where docker logs shows it; nothing rotates a file inside a container, so no file is written unless XMQ_LOG_FILE=keep asks for one. Client connections appear only when the connect and disconnect log categories are set to DEBUG in the configuration interface.

The load generators xmq_pub, xmq_sub, xmq_con and the scenario runner xmq_scn are in the image, so a broker can be driven from a second container with nothing else installed. The accounts file of the package is not: it carries known passwords, and the server writes a fresh one on first start instead.

⁠Performance

Median latency with 50 000 publishers at 50k msg/s (AWS c5n.4xlarge, MQTT 5, QoS 1):

Full results, methodology and raw output: https://xmq.sptk.net⁠.

Documentation and downloads: https://xmq.sptk.net⁠.