Docker Compose Permission Denied

Docker compose is one of the most useful tools in the ecosystem. It provides us with extensive features for defining and running multi-container applications. Using Docker compose, we can define all the requirements and configuration of our containerized applications. We can then use the tool to create an image based on those configurations. Using Docker Compose, we can distribute the created image and customize it with ease.

As you can guess, some of the configuration of Docker compose is to set up app requirements such as networks, volumes, services, and more. This does require performing privilege operations on the host system.

Therefore, when working with Docker compose, you may encounter permission-related issues, particularly “Permission Denied” errors.

In this tutorial, we will explore the common cause of the permission denied error in Docker compose and provide you with potential solutions to resolve it.

Common Causes of Permission Denied Error

One of the major causes of the ‘permission denied’ error when working with Docker compose depends on the container configuration. However, some potential causes include

1. Writing to a directory where the host user lacks write permissions.
2. Volume permission error – another cause of a permission denied error is when the user defined in the container does not have sufficient permissions to access the volume or has incorrect volume ownership.
3. Network configurations – and lastly, a possible cause of a permission denied error in docker compose is setting up services in the container that need to communicate with external resources. Defining such objects with the correct permissions can lead to such errors.

Resolve Docker Permission Denied Error.

The following are some of the steps you can take to resolve the permission denied error when working in Docker Compose.

Run the Commands with Sudo

If you have sudo or root access on the host machine, the most common solution to the permission denied error is running the docker compose commands as the root user.

Adjust Container User Permissions

However, if you do not have root or sudo permissions on the host machine, you can resolve the permission denied error by adjusting the container user permission in the Dockerfile.

Some options you can apply in the Dockerfile include:

• Use the user directive in the Dockerfile to specify a non-root user for the application inside the container.
• Match the container user’s UID and GID with the host user to avoid permission mismatches.

Fix Volume Ownership

As you can guess, volume permissions and configuration are potential causes of permission denied in the Docker compose file.

To resolve such issues, you can take the following steps:

1. Use named volumes for better control over permissions and ownership.
2. Ensure that the UID and GID of the container match those of the host user.
3. Adjust file permissions inside the container.

Conclusion

In this tutorial, we learned about the permission denied error when working with the Docker Compose utility. We learned some potential causes of the command and possible solutions.