How to Install GitLab on Docker: Simplified Instructions

Setting up GitLab using Docker might seem tricky, but it’s actually pretty simple. With Docker, you can quickly get a GitLab server running on your machine. This guide will walk you through the steps to install and configure GitLab using Docker and Docker Compose. We’ll also cover some common issues and how to solve them.

Key Takeaways

• Docker makes it easy to set up a GitLab server on your local machine.
• You can use Docker Compose to manage your GitLab setup more efficiently.
• Handling SELinux and adjusting permissions are crucial for a smooth GitLab installation.
• Always back up your GitLab data before making upgrades or changes.
• Troubleshooting common issues like port conflicts and permission errors can save you a lot of time.

Setting Up Your Environment

Before you can install GitLab on Docker, you need to set up your environment properly. This involves installing Docker, configuring it for GitLab, and setting up the necessary environment variables. Let’s break it down step by step.

Running GitLab with Docker Engine

Pulling the GitLab Image

First things first, you need to pull the GitLab image from Docker Hub. Open your terminal and run:

sudo docker pull gitlab/gitlab-ee:latest

This command fetches the latest GitLab Enterprise Edition image. If you prefer the Community Edition, replace gitlab-ee with gitlab-ce.

Running the Container

Now that you have the image, it’s time to run the container. Use the following command:

sudo docker run --detach \
  --hostname gitlab.example.com \
  --publish 443:443 --publish 80:80 --publish 22:22 \
  --name gitlab \
  --restart always \
  --volume $GITLAB_HOME/config:/etc/gitlab \
  --volume $GITLAB_HOME/logs:/var/log/gitlab \
  --volume $GITLAB_HOME/data:/var/opt/gitlab \
  --shm-size 256m \
  gitlab/gitlab-ee:latest

This command starts a GitLab container and publishes the necessary ports for SSH, HTTP, and HTTPS. All GitLab data will be stored in subdirectories of $GITLAB_HOME. The container will automatically restart after a system reboot.

Accessing GitLab

Once the container is up and running, you can access GitLab by visiting http://gitlab.example.com in your web browser. It might take a few minutes for the container to be fully operational.

To get the initial root password, run:

sudo docker exec -it gitlab grep 'Password:' /etc/gitlab/initial_root_password

Use this password to log in with the username root. Remember to change the root password after your first login for security reasons.

Tip: If you’re using SELinux, append :Z to the volume paths to ensure proper permissions.

And that’s it! You’ve successfully set up GitLab using Docker Engine. If you encounter any issues, check the container logs with:

sudo docker logs -f gitlab

Using Docker Compose for GitLab

Docker Compose makes it super easy to set up and manage your GitLab instance. Follow these steps to get started quickly.

Handling SELinux and Permissions

Running GitLab on SELinux

To run GitLab on a system with SELinux, you need to make sure SELinux policies are correctly configured. SELinux can block some of the operations GitLab needs to perform. Use the following command to set the correct context for GitLab directories:

sudo chcon -Rt svirt_sandbox_file_t /srv/gitlab

This command ensures that GitLab has the necessary permissions to read and write to its directories.

Adjusting Volume Permissions

When using Docker, volume permissions can sometimes cause issues. To avoid these, set the correct permissions for your GitLab volumes. Use the chmod command to adjust permissions:

sudo chmod -R 755 /srv/gitlab

This command makes sure that GitLab can access its volumes without any permission issues.

Tracking Initialization

After setting up SELinux and adjusting volume permissions, it’s important to track the initialization process. Check the logs to ensure everything is running smoothly. Use the following command to view the logs:

docker logs -f gitlab

This command will show you real-time logs, helping you identify any issues during the initialization process.

Tip: Always keep an eye on the logs to catch any potential problems early.

Managing GitLab Post-Installation

Accessing GitLab for the First Time

After installing GitLab, you need to access it for the first time. Open your browser and go to the URL you set during installation. If you didn’t set a custom password, a random one is generated and stored in /etc/gitlab/initial_root_password. Use this password with the username root to log in.

Setting Up the Root Password

Once logged in, it’s crucial to set a secure root password. Navigate to the settings and change the password to something strong and memorable. Don’t skip this step; it’s vital for your GitLab’s security.

Configuring External URL

To make your GitLab instance accessible, you need to configure the external URL. This is the address where users will access GitLab. Update the EXTERNAL_URL in the GitLab configuration file and restart the service. This ensures that your GitLab is reachable from the internet.

Remember, setting up your environment correctly is key to a smooth GitLab experience. Double-check your settings to avoid any issues later on.

Upgrading and Maintaining GitLab

Backing Up GitLab

Before making any changes, it’s crucial to back up your GitLab instance. Use the built-in backup tool to create a snapshot of your data. This ensures you can restore your projects and repositories if something goes wrong. Run the following command to create a backup:

sudo gitlab-rake gitlab:backup:create

Store the backup file in a safe location, preferably offsite or in a different storage system.

Upgrading the Docker Image

To upgrade GitLab to the latest version, you need to stop and remove the current container, pull the new image, and recreate the container. Follow these steps:

1. Stop the running container:
2. Remove the container:
3. Pull the latest GitLab image:
4. Recreate the container with the new image:

Remember to replace gitlab.example.com with your actual hostname.

Restarting the Container

If you need to restart the GitLab container for any reason, use the following command:

sudo docker restart gitlab

This command will stop and then start the container, applying any new configurations or updates.

Regular maintenance and updates are essential to keep your GitLab instance secure and running smoothly. Always test updates in a staging environment before applying them to production.

By following these steps, you can ensure your GitLab instance is always up-to-date and well-maintained. This will help you take full advantage of GitLab’s features and keep your development process running smoothly.

Troubleshooting Common Issues

Dealing with Port Conflicts

Port conflicts can be a real headache when running GitLab on Docker. If you encounter this issue, the first step is to check which ports are already in use. Use the netstat or ss command to list all active ports. Change the port in your Docker run command or Docker Compose file to avoid conflicts. Sometimes, simply restarting the Docker service can resolve the issue.

Fixing Volume Mount Errors

Volume mount errors often occur due to incorrect file paths or permission issues. Ensure that the paths specified in your Docker command or Docker Compose file are correct. If you still face issues, check the permissions of the directories. Running chmod to adjust permissions can often fix these errors. Remember, Docker needs the right permissions to access your files.

Resolving Permission Issues

Permission issues can prevent GitLab from running smoothly. These issues often arise when Docker doesn’t have the necessary permissions to access certain files or directories. To fix this, you can run Docker commands with sudo or adjust the permissions using chmod and chown. Ensuring proper permissions is crucial for a smooth GitLab experience.

Troubleshooting can be frustrating, but with the right steps, you can resolve most issues quickly and efficiently.

Frequently Asked Questions

What are the basic steps to install GitLab on Docker?

First, you need to install Docker. Next, pull the GitLab image from the Docker repository. Finally, run the GitLab container using the appropriate commands.

How do I access GitLab after installation?

You can access GitLab by visiting the URL you set during the installation process. The default username is ‘root,’ and you can find the initial password using a Docker command.

What should I do if I encounter a port conflict?

If you run into a port conflict, you can change the port settings in your Docker run command or Docker Compose file to use different ports.

Can I use Docker Compose to install GitLab?

Yes, you can use Docker Compose to install GitLab. You’ll need to create a docker-compose.yml file with the necessary configuration and then run ‘docker-compose up -d’.

How do I handle permissions issues with GitLab on Docker?

Permissions issues can often be resolved by adjusting the volume permissions in your Docker commands or Docker Compose file. For SELinux users, adding the ‘:Z’ flag to volume mounts can help.

What is the best way to back up my GitLab data?

The best way to back up your GitLab data is to use the built-in backup tools provided by GitLab. You can also back up the volumes used by your Docker container.