NATS

What is NATS?

NATS is a lightweight, high-performance messaging system for cloud-native and microservice architectures, used for pub/sub, request/reply, and simple queueing. Laradock runs the official nats image with its own config file baked in.

Start NATS

Laradock CLI

./laradock start nats

Docker Compose

docker compose up -d nats

Stop NATS

Stopping just pauses the container. NATS in this setup keeps no persistent data volume, so there's nothing to preserve or lose either way:

Laradock CLI

./laradock stop nats

Docker Compose

docker compose stop nats

To delete the container entirely:

Laradock CLI

./laradock remove nats

Docker Compose

docker compose rm -sf nats

Configuration

All settings live in nats/defaults.env and can be overridden by adding the same line to your own .env:

Variable	Default	What it does
NATS_CLIENT_PORT	4222	Host-side port for client connections.
NATS_MONITORING_PORT	6222	Host-side port for the clustering route port (mapped from the container's 6222).
NATS_ROUTE_PORT	8222	Host-side port for the HTTP monitoring endpoint (mapped from the container's 8222).

The container's own nats-server.conf (baked into the image via nats/Dockerfile) sets the client port to 4222, the HTTP monitoring port to 8222, and a cluster block on port 6222 for connecting multiple NATS servers together. Note the naming in defaults.env doesn't line up 1:1 with what each port actually does inside the container: NATS_MONITORING_PORT maps to the container's clustering port 6222, and NATS_ROUTE_PORT maps to the container's HTTP monitoring port 8222. Double-check nats/compose.yml if you rely on a specific one.

Change the server config

nats/nats-server.conf is copied into the image at build time (COPY nats-server.conf /etc/nats/nats-server.conf in nats/Dockerfile), so editing it needs a rebuild, a plain restart won't pick up the change. After editing the file:

Laradock CLI

./laradock rebuild nats
./laradock start nats

Docker Compose

docker compose build nats
docker compose up -d nats

Enable clustering

nats-server.conf ships with an empty routes = [] list, so clustering to other NATS servers is off by default. To connect this server to others, add their nats-route:// addresses to routes in nats/nats-server.conf and rebuild (see above). The cluster block's built-in authorization credentials for route connections are ruser / T0pS3cr3t, change these in nats-server.conf before exposing the cluster port (NATS_MONITORING_PORT, container 6222) beyond your own machine. Full options are in the NATS clustering docs.

Connect from your app

Inside Laradock, other containers reach NATS by container name and its internal client port: nats:4222. From your host machine, connect to localhost:4222 (or your custom NATS_CLIENT_PORT) with any NATS client library.

Check server health

The HTTP monitoring endpoint (container port 8222, published on NATS_ROUTE_PORT by default) serves NATS's built-in monitoring JSON:

curl http://localhost:8222/varz

A few other endpoints on the same port are useful day-to-day:

Endpoint	Shows
/varz	General server stats: uptime, connections, memory, CPU.
/connz	Currently connected clients.
/subsz	Active subscriptions.
/routez	Cluster route connections (relevant once clustering is set up).

View logs

Laradock CLI

./laradock logs nats

Docker Compose

docker compose logs --tail=100 nats

Talk to this NATS server from another Laradock project

Each Laradock project is its own isolated Docker network by default, so a second project's containers can't reach this NATS by container name out of the box. Since the client port is already published (NATS_CLIENT_PORT), the other project can connect to your host machine's address instead of nats, for example host.docker.internal:4222 (Docker Desktop) using this project's NATS_CLIENT_PORT. Make sure the two projects use different NATS_CLIENT_PORT values if they're both running at once.

Common issues

• Port already in use on your host. Another local NATS instance (or another Laradock project) is already bound to one of the default ports. Change the relevant NATS_*_PORT variable in .env and restart: ./laradock restart nats.
• Monitoring/route ports feel swapped. As noted above, NATS_MONITORING_PORT and NATS_ROUTE_PORT don't map to the container ports their names imply; check nats/compose.yml and nats/nats-server.conf directly if a specific port matters to you.
• Clustering doesn't work out of the box. nats-server.conf ships with an empty routes = [] list; see Enable clustering above.
• Config changes don't take effect. nats-server.conf is copied into the image at build time, so a plain restart won't pick up edits, see Change the server config above.

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Need a message queue with a management UI instead? See RabbitMQ. New to Laradock? Start at Getting Started.