How to Fix Docker: Permission Denied

If you've run into a permission denied error with Docker, you're not alone. Whether you're trying to run docker without sudo, mount a volume, or access a file inside the container, this error is one of the most common stumbling blocks.

In this guide, we'll walk through how to fix Docker permission denied issues depending on the context and your operating system.

Prerequisites

Before you start, make sure:

• Docker is installed and the service is running
• You have access to a terminal with sufficient permissions

Scenario 1: Running docker Without sudo Gives Permission Denied

If you get a permission error like this:

Got permission denied while trying to connect to the Docker daemon socket

It usually means your user isn't in the docker group.

Fix:

1. Add your user to the Docker group:

sudo usermod -aG docker $USER

2. Log out and log back in (or reboot) to apply the group change.

3. Verify with:

groups $USER

4. Test without sudo:

docker ps

You should no longer see the error.

Scenario 2: Permission Denied When Mounting a Volume

If you see an error like:

Error response from daemon: Mounts denied

This is common on macOS or Windows when you're trying to mount a local directory into a container.

Fix (macOS/Windows):

1. Open Docker Desktop > Settings > Resources > File Sharing
2. Make sure the directory you're trying to mount is listed

If it's not, add it and restart Docker.

Fix (Linux):

Make sure the directory exists and has the correct permissions:

mkdir -p /my/data
sudo chown $USER:$USER /my/data

Then run:

docker run -v /my/data:/app/data my-image

Scenario 3: Permission Denied on a File Inside the Container

Sometimes your app can't access a file inside the container due to restrictive permissions.

Fix:

Check file permissions and ownership in your Dockerfile or entrypoint script. You can add:

RUN chmod -R 755 /app && chown -R appuser:appuser /app

Or debug live with:

docker exec -it my-container bash
ls -l /path/to/file

Adjust as needed using chmod or chown.

Bonus: AppArmor and SELinux

On some Linux systems, you might hit issues due to AppArmor or SELinux blocking access silently.

If you're using SELinux (e.g. on CentOS, RHEL, Fedora), try adding the :z or :Z flags when mounting:

docker run -v /host/data:/container/data:Z my-image

This adjusts security contexts automatically.

Still Not Working?

Check Docker logs for more context:

journalctl -u docker.service

Or try running the command with sudo to isolate whether it's a user permission issue or something deeper.

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Permission denied errors in Docker are common but fixable. Whether it's your user group, a volume mount, or file ownership, the key is to identify where the access is blocked and adjust accordingly.

Once you get familiar with the patterns, solving these becomes second nature.