Skip to content

How to Use Docker-Compose

Installing Docker

Use docker.io, which packages the docker engine in the debian/ubuntu philosophy (multi-package):

$ sudo apt install docker.io

Installing Docker-Compose:

$ sudo curl -o /usr/local/bin/docker-compose -L "https://github.com/docker/compose/releases/download/${DOCKER_VERSION}/docker-compose-$(uname -s)-$(uname -m)"

$ sudo chmod +x /usr/local/bin/docker-compose

where ${DOCKER_VERSION} is the latest release ID.

Running a Docker-Compose File:

  1. CD into the directory with the docker-compose YAML
  2. Pull the latest images for the applications defined in the docker-compose file, then launch a new container:
$ docker-compose pull

  pulling [image]...done

$ docker-compose up -d
Note

The -d switch means to run the container in detached mode; important if you want to disconnect from the terminal or issue other commands

Updating a Docker-Compose App

  1. Pull the latest image and recreate the containers:
$ docker-compose pull

  pulling [image]...done

$ docker-compose up --force-recreate -d
Note

You can also recreate a specific container by passing its name into the docker-compose up command like so: docker-compose up --force-recreate -d <container-name>

Checking What Docker Containers Are Running

You can inspect what's running like so:

docker ps

This will produce the names of the running containers and details about them (including uptime and healthchecks, where applicable).

Stopping a Running Container

You can stop a container like so:

  1. Use docker ps to get the ID of the container
  2. Stop the container:
docker container stop <container-name>

Cleaning Out Old Containers, Volumes, and Images

After pulling a new image, recreating the container, and verifying that the new app image runs well, it's a good idea to wipe the old data from the system. This will free up TONS of disk space as docker images can be several hundreds of megabytes large:

  1. Make sure everything is running before issuing the following command. It is destructive for anything not currently referenced by a running container:
docker system prune -af
Last update: 2022-12-30