Docker CentOS no space left on device - Shell/Bash

Introduction

As a software developer, you may have encountered a scenario where you hit the error message no space left on device when working with Docker and CentOS. This error occurs when your Docker container runs out of disk space. It often happens when you are working with large files or processing a lot of data.

This guide will walk you through the steps to diagnose and resolve the issue.

Diagnosis

First, you need to determine whether your Docker container is running out of disk space. You can do this by running the following command:

df -h

This command will display the disk usage and available space of your Docker container's file system.

If you see that your Docker container is running out of disk space, you can investigate further by running the following command:

du -hs /*

This command will display the disk usage of each directory in the root directory.

Resolution

Clean up Docker cache

The easiest way to resolve this issue is to clean up the Docker cache. You can do this by running the following command:

docker system prune

This command will remove all unused containers, images, and networks, freeing up much-needed disk space.

Increase the disk size of your Docker container

If cleaning up the Docker cache doesn't free up enough disk space, you may need to increase the disk size of your Docker container. You can do this by running the following command:

docker run -it --device /dev/sdb centos /bin/bash

This command will create a new Docker container with an additional disk mounted at /dev/sdb.

You will then need to format and partition the new disk using the following commands:

fdisk /dev/sdb
mkfs.ext4 /dev/sdb1

Finally, mount the new disk with the following command:

mount /dev/sdb1 /mnt/docker

The new disk will now be available for use by your Docker container.

Conclusion

In summary, the error message no space left on device can be caused by a lack of disk space in your Docker container. You can resolve this issue by cleaning up the Docker cache or by increasing the disk size of your Docker container. I hope this guide was helpful in resolving the issue.