- Docker can package an application and its dependencies in a virtual container that can run on any Linux, Windows, or macOS computer. This enables the application to run in a variety of locations, such as on-premises, in a public cloud, and/or in a private cloud. Use this script to install Docker and Docker Compose.
- Install the latest version of Docker CE. $ sudo apt-get -y install docker-ce. Docker should now be installed, the daemon started, and the process enabled to start on boot. Check that it's running: $ sudo systemctl status docker. Verify that Docker CE is installed correctly by running the hello-world image.
Installing Docker Installing Docker with WSL2. First, start Ubuntu. Press the windows key and put in “Ubuntu” to get a suggestion, then click on it to launch the terminal. Docker installed on your server or local machine, following Steps 1 and 2 of How To Install and Use Docker on Ubuntu 20.04. Step 1 — Installing Docker Compose. To make sure we obtain the most updated stable version of Docker Compose, we’ll download this software from its official Github repository.
Docker is a great tool for automating the deployment of Linux applications inside software containers, but to take full advantage of its potential each component of an application should run in its own individual container. For complex applications with a lot of components, orchestrating all the containers to start up, communicate, and shut down together can quickly become unwieldy.
The Docker community came up with a popular solution called Fig, which allowed you to use a single YAML file to orchestrate all your Docker containers and configurations. This became so popular that the Docker team decided to make Docker Compose based on the Fig source, which is now deprecated. Docker Compose makes it easier for users to orchestrate the processes of Docker containers, including starting up, shutting down, and setting up intra-container linking and volumes.
In this tutorial, we’ll show you how to install the latest version of Docker Compose to help you manage multi-container applications.
To follow this article, you will need an Ubuntu 18.04 server with the following:
- A non-root user with sudo privileges (Initial Server Setup with Ubuntu 18.04 explains how to set this up.)
- Docker installed with the instructions from Step 1 and Step 2 of How To Install and Use Docker on Ubuntu 18.04
Once these are in place, you’re ready to follow along.
Install Docker And Docker Compose On Ubuntu
Note: Even though the Prerequisites give instructions for installing Docker on Ubuntu 18.04, the
docker commands in this article should work on other operating systems as long as Docker is installed.
Step 1 — Installing Docker Compose
Although we can install Docker Compose from the official Ubuntu repositories, it is several minor version behind the latest release, so we’ll install Docker Compose from the Docker’s GitHub repository. The command below is slightly different than the one you’ll find on the Releases page. By using the
-o flag to specify the output file first rather than redirecting the output, this syntax avoids running into a permission denied error caused when using
We’ll check the current release and if necessary, update it in the command below:
Next we’ll set the permissions:
Then we’ll verify that the installation was successful by checking the version:
This will print out the version we installed:
Now that we have Docker Compose installed, we’re ready to run a “Hello World” example.
Step 2 — Running a Container with Docker Compose
The public Docker registry, Docker Hub, includes a Hello World image for demonstration and testing. It illustrates the minimal configuration required to run a container using Docker Compose: a YAML file that calls a single image:
First, we’ll create a directory for the YAML file and move into it:
Then, we’ll create the YAML file:
Put the following contents into the file, save the file, and exit the text editor:
The first line in the YAML file is used as part of the container name. The second line specifies which image to use to create the container. When we run the command
docker-compose up it will look for a local image by the name we specified,
hello-world. With this in place, we’ll save and exit the file.
We can look manually at images on our system with the
docker images command:
When there are no local images at all, only the column headings display:
Now, while still in the
~/hello-world directory, we’ll execute the following command:
The first time we run the command, if there’s no local image named
hello-world, Docker Compose will pull it from the Docker Hub public repository:
After pulling the image,
docker-compose creates a container, attaches, and runs the hello program, which in turn confirms that the installation appears to be working:
Then it prints an explanation of what it did:
Docker containers only run as long as the command is active, so once
hello finished running, the container stopped. Consequently, when we look at active processes, the column headers will appear, but the
hello-world container won’t be listed because it’s not running.
We can see the container information, which we’ll need in the next step, by using the
-a flag which shows all containers, not just the active ones:
This displays the information we’ll need to remove the container when we’re done with it.
Step 3 — Removing the Image (Optional)
To avoid using unnecessary disk space, we’ll remove the local image. To do so, we’ll need to delete all the containers that reference the image using the
docker rm command, followed by either the CONTAINER ID or the NAME. Below, we’re using the CONTAINER ID from the
docker ps -a command we just ran. Be sure to substitute the ID of your container:
Once all containers that reference the image have been removed, we can remove the image:
We’ve now installed Docker Compose, tested our installation by running a Hello World example, and removed the test image and container.
Docker Compose Installation
While the Hello World example confirmed our installation, the simple configuration does not show one of the main benefits of Docker Compose — being able to bring a group of Docker containers up and down all at the same time. To see the power of Docker Compose in action, you might like to check out this practical example, How To Configure a Continuous Integration Testing Environment with Docker and Docker Compose on Ubuntu 16.04(note: this article is for Ubuntu 16.04 rather than 18.04)