Introduction

Docker is a powerful tool that allows you to create and manage containers on your system. However, running Docker as the root user can pose a security risk. In this article, we will discuss how to add a nonroot user to administer Docker. By doing so, you will be able to run Docker commands without having to log in as the root user, which can help to improve the security of your system.

Why Run Docker as a Non-root User?

There are several reasons why you may want to run Docker as a nonroot user. One of the main reasons is security. Running Docker as the root user can pose a security risk as it gives the user full access to the system. This means that if a hacker were to gain access to the system, they would have full control over it.

Another reason to run Docker as a nonroot user is to prevent accidental changes to the system. When you run Docker as the root user, you have the ability to make changes to the system without any restrictions. This can be dangerous if you accidentally delete or change important files.

Finally, running Docker as a nonroot user can help to improve the performance of your system. When you run Docker as the root user, the system uses more resources as it needs to run the Docker daemon as well as other processes. By running Docker as a nonroot user, you can reduce the amount of resources that the system uses, which can help to improve the performance of your system.

Creating a Non-root User

The first step in adding a nonroot user to administer Docker is to create a new user. This can be done by using the “useradd” command. The useradd command is used to create a new user on your system.

The syntax for the useradd command is as follows:

useradd [options] username

For example, to create a new user called “docker”, you would use the following command:

useradd -m docker

The -m option is used to create a new home directory for the user.

Once the user has been created, you will need to set a password for the user. This can be done using the “passwd” command. The syntax for the passwd command is as follows:

passwd username

For example, to set a password for the “docker” user, you would use the following command:

passwd docker

You will then be prompted to enter and confirm a new password for the user.

Adding a Non-root User to the Docker Group

Once the nonroot user has been created, you will need to add the user to the Docker group. The Docker group is a special group on your system that is used to manage access to Docker. By adding the nonroot user to this group, you will be able to run Docker commands without having to log in as the root user.

To add the user to the Docker group, you will need to use the “usermod” command. The syntax for the usermod command is as follows:

usermod -a -G groupname username

For example, to add the “docker” user to the Docker group, you would use the following command:

usermod -a -G docker docker

The -a option is used to append the user to the specified group. The -G option is used to specify the group that the user should be added to.

Testing the Non-root User

Once the nonroot user has been added to the Docker group, you can test to see if the user can run Docker commands without logging in as the root user. To do this, you will need to log out of your current user and log in as the non-root user. Once logged in, you can run a simple Docker command, such as “docker info”, to see if the user has the necessary permissions to run Docker commands.

If the command runs successfully, it means that the nonroot user has been added to the Docker group and can run Docker commands without logging in as the root user. If the command returns an error, it means that there is an issue with the user’s permissions and you will need to troubleshoot further.

Conclusion

Running Docker as a non-root user can improve the security and performance of your system. By adding a non-root user to administer Docker, you can run Docker commands without having to log in as the root user, which can help to reduce the risk of accidental changes to the system and improve the performance of your system. By following the steps outlined in this article, you can easily add a non-root user to administer Docker on your system. Remember that, to run your container you will have to use “sudo” before the command.