How to Setup Docker Private Registry on Ubuntu 18.04

In this tutorial, we will learn how to setup your own private Docker registry on Ubuntu 18.04 server. We will setup one server as a Docker registry server and other server as a registry client to push and pull image from the registry server.

Requirements

• Two servers with Ubuntu 18.04 server installed on both.
• A static IP address 192.168.0.102 is set up on registry server and 192.168.0.103 is set up on the registry client.
• A root password is set up on both servers.

Getting Started

First, you will need to update both servers with the latest version. You can update them by running the following command:

Once both servers are updated, restart them to update all the changes.

Next, you will need to configure hostname resolution on both servers. So, both server can communicate with each other using hostname.

You can do it by editing /etc/hosts file.

Open /etc/hosts file on both server with the following command:

Add the following lines:

Save and close the file, when you are finished.

Next, you will also need to install some required packages to your server. You can install all of them with the following command:

Install Docker

Next, you will need to install Docker on both servers. By default, the latest version of Docker is not available in the Ubuntu 18.04 server default repository. So, you will need to add the repository for that.

First, download and add Docker CE GPG key with the following command:

Next, add the Docker CE repository to APT with the following command:

Add the following line:

Save and close the file, when you are finished. Then, update the repository with the following command:

Once the repository is updated, install Docker CE with the following command:

After installing Docker CE, check the Docker service with the following command:

You should see the following output:

Install Registry Server

Docker is now installed and running on both servers. It’s time to download and install registry server on Docker server. You can download the registry image from Docker Hub by running the following command:

You should see the following output:

Docker uses a secure connection over TLS to push and pull images from the registry server. So, you will need to generate a self signed certificate secure Docker registry.
 
First, create a directory to store certificates with the following command:

Next, generate a self signed certificates with the following command:

Answer all the questions as shown below:

Next, start the Docker registry container with generated certificate information as shown below:

You can now verify the running registry container with the following command:

You should see the following output:

Setup Docker Registry Client

Next, you will need to create a Docker image on Docker client server. We will upload this image on Registry server later.

First, create a docker directory with the following command:

Next, create a dockerfile to build an Apache image:

Add the following lines:

Now, run the following command to build an Apache docker image using dockerfile:

You should see the following output:

Next, you will need to rename the generated image in “registryserver:portnumber/image name:tag” format. You can do this with the following command:

You can now list all the images with the following command:

You should see the following output:

Push Docker Image on Registry Server

Docker registry server and client are now ready to use. It’s time to push image to Docker server.

First, you will need to copy the ca.crt certificate from the docker-server to the docker-client. First, create a directory to store certificate with the following command:

Next, copy ca.crt from docker-server with the following command:

Next, restart Docker server to apply all the changes with the following command:

Next, push the Apache docker image to the Docker registry server with the following command:

You should see the following output:

Now, log in to other system and pull the uploaded image from the registry server using the following command:

You should see the following output:

Thats It. You can now build more images and upload them on registry server. You can pull those images on other clients any time from the registry server.