How to fix (Got permission denied while trying to connect to the Docker daemon socket)

Fix Docker Permission Denied Error

The Permission Denied error in Docker happens when a non-root user without enough privileges tries to run a Docker command. This error usually appears after installing or updating Docker, or when changes are made to users or groups on your system.

If you prefer a step-by-step walkthrough, watch the video tutorial below:

In this guide, I'll walk you through six ways to fix the "Permission Denied" error in Docker, ranging from simple fixes like restarting Docker to more advanced ones, like adjusting file permissions.

Prerequisites

• Docker installed.
• Admin access to your system.

What is Docker Permission Denied Error?

The error occurs when the system can't communicate with Docker because the user doesn't have the required privileges. Below is an example of the error when attempting to list Docker images:

docker images
Error response from daemon: Got permission denied while trying to connect to the Docker daemon socket...

Let's dive into the possible solutions:

Method 1: Restart Docker

Restarting Docker might be enough to solve the issue. Use this command:

sudo service docker restart

To check if Docker restarted successfully, run:

service docker status

If the Active field says "active", Docker is running. Test by running the docker images command again.

Method 2: Run Docker Commands with sudo

The error usually happens for non-root users. You can fix it by adding sudo to your Docker command, like this:

sudo docker run hello-world

Method 3: Enable Non-Root User Access

If you don't want to use sudo every time, follow these steps to give non-root users Docker access:

1. Create the Docker group:

sudo groupadd -f docker

2. Add your user to the Docker group:

sudo usermod -aG docker $USER

3. Apply the changes to your current session:

newgrp docker

4. Check if the Docker group is added:

groups

If all went well, you should now be able to run Docker commands without sudo. If the error persists, try restarting your system.

Method 4: Review File Permissions

If adding your user to the Docker group didn’t fix it, you might need to adjust file permissions:

1. Change the ownership of the docker.sock file:

sudo chown root:docker /var/run/docker.sock

2. Ensure you own the .docker directory:

sudo chown -R "$USER":"$USER" $HOME/.docker

3. Give group read and write permissions:

sudo chmod -R g+rw "$HOME/.docker"

Note: The .docker directory is created when you log into Docker Hub using the docker login command. If you get an error saying "No such file or directory", you can ignore it.

Method 5: Edit Docker Service File

If you're still seeing the error, you might need to edit the Docker service file:

1. Open the file using Nano:

sudo nano /usr/lib/systemd/system/docker.service

2. Add these lines to the bottom of the "Service" section:

SupplementaryGroups=docker
ExecStartPost=/bin/chmod 666 /var/run/docker.sock

3. Save the file and exit. Restart Docker (refer to Method 1).

Method 6: Run Docker in Privileged Mode

Warning: This method is not recommended for production environments. Privileged mode gives the container root-level access.

To check if your container is running in privileged mode:

1. List all containers:

sudo docker ps -a

2. Check if your container is privileged:

sudo docker inspect --format='{{.HostConfig.Privileged}}' [container-id]

3. If you need to create a privileged container, run:

sudo docker run -d --privileged nginx

Conclusion

There are multiple ways to fix the Docker "Permission Denied" error, from restarting Docker to adjusting file permissions. For more complex troubleshooting, check Docker's built-in logging tools.