🚀 Setting Up a Private Docker Registry in Nexus

Managing your own private Docker registry can be a game-changer for secure, fast, and efficient container deployments. In this blog, we’ll guide you through setting up a private Docker registry using Nexus step by step. Follow along to ensure your registry is up and running smoothly! 🎉

1️⃣ Install Docker 🐳

Before we dive in, ensure Docker is installed on your machine. Follow the instructions for your operating system on the Docker official site.
Verify installation:

sudo apt install docker.io
docker --version

2️⃣ Add Nexus URL to Insecure Registries 🔒

If you're hosting Nexus without SSL (not recommended for production):

1. Locate Docker’s daemon.json file (usually in /etc/docker/daemon.json on Linux or C:\ProgramData\docker\config\daemon.json on Windows).

2. Add your Nexus server URL under insecure-registries:

    {
      "insecure-registries": ["<your-nexus-url>:<port>"]
    }
   

   

3. Restart Docker to apply changes:

    sudo systemctl restart docker  # Linux
   

   

3️⃣ Set Up Nexus Using a Docker Container 🛠️

Run Nexus as a Docker container:

docker run -d -p 8081:8081 -p 5000:5000 --name nexus sonatype/nexus3

Access Nexus via your browser at http://<your-server-ip>:8081. Log in using the default credentials:

• Username: admin

• Password: Found in the file /nexus-data/admin.password inside the container.

4️⃣ Create a Docker Hosted Repository in Nexus 🏗️

1. Navigate to Repositories in the Nexus UI.

2. Click Create repository → Select Docker (hosted).

3. Configure the following:

   • Name: docker-private

   • HTTP Port: Specify a port (e.g., 5000).

4. Save the repository.

   

5️⃣ Enable Docker Bearer Token Authentication 🔑

1. Go to Administration → Security → Realms.

2. Activate Docker Bearer Token Realm by moving it to the active realms list.

3. Save the settings.

   

6️⃣ Log In to the Private Docker Registry 📝

Authenticate with the private registry:

bashCopy codedocker login <your-nexus-url>:<port>

Provide your Nexus credentials.

7️⃣ Tagging an Image 🏷️

Let’s tag a local Docker image for your private registry:

docker tag <local-image>:<tag> <your-nexus-url>:<port>/<repo-name>/<image_name>:<tag>

For example:

docker tag nginx:latest localhost:5000/docker-private/nginx-latest

8️⃣ Push an Image to the Private Repository 📤

Push the tagged image to your private registry:

docker push <your-nexus-url>:<port>/<repo-name>:<tag>

Example:

docker push localhost:5000/docker-private:nginx-latest

9️⃣ Pull a Public Image, Tag, and Push to Nexus 🛳️

1. Pull a public image from Docker Hub:

    docker pull busybox:latest
   

   

2. Tag it for your private registry:

    docker tag busybox:latest localhost:5000/docker-private/busybox:latest
   

3. Push the tagged image:

    docker push localhost:5000/docker-private/busybox:latest
   

   

🔟 Remove Local Image and Pull from Private Registry 🗑️⬇️

1. Remove the image from your local machine:

    docker rmi <your-nexus-url>:<port>/<repo-name>:<tag>
   

   Example:

    docker rmi localhost:5000/docker-private:nginx-latest
   

2. Pull the image from your private registry to verify:

    docker pull <your-nexus-url>:<port>/<repo-name>:<tag>
   

   Example:

    docker pull localhost:5000/docker-private:nginx-latest
   

   

🎉 All Set!

You now have a fully functional private Docker registry hosted on Nexus. You can securely push, pull, and manage Docker images in your repository. 🏆 Happy containerizing! 🚢