How to Install and Use Docker on Your Ubuntu Server 24.04 VPS

2024-07-08

Hey folks! If you’re like me, you might be exploring Docker to manage your applications more efficiently on your Ubuntu Server 24.04 VPS. In this post, I’ll show you how I installed Docker and how you can get started using it.

Why Docker?

Portability: Your Docker containers will run the same way locally or on any cloud platform.
Isolation: This is key! Each container runs in its own little world, preventing conflicts and improving security.
Security: By keeping Docker isolated, you reduce potential attack surfaces.
Cleanliness: Your VPS stays tidy since applications are contained.

Let’s Get It Done!

Prerequisites

A freshly installed Ubuntu 24.04 VPS
Basic Linux command-line knowledge
A user account with sudo privileges
An SSH connection to your server

Step 1: System Update

Before we start, let’s make sure your system is up-to-date:

sudo apt update && sudo apt upgrade

Expected Output: You’ll see a list of packages being checked and potentially upgraded. If there are updates, you’ll be prompted to confirm the installation.

Step 2: Install Docker

We’ll use the official Docker repository to get the latest version:

# Add Docker's official GPG key:
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo gpg --dearmor -o /usr/share/keyrings/docker-archive-keyring.gpg
# Expected output: OK

# Add the Docker repository:
echo "deb [arch=$(dpkg --print-architecture) signed-by=/usr/share/keyrings/docker-archive-keyring.gpg] https://download.docker.com/linux/ubuntu $(lsb_release -cs) stable" | sudo tee /etc/apt/sources.list.d/docker.list > /dev/null

# Update the package index again:
sudo apt update

# IMPORTANT: Verify you're pulling from the correct repository
apt-cache policy docker-ce

Expected Output:

docker-ce:
  Installed: (none)
  Candidate: 5:24.0.5-1~ubuntu24.04~lunar
  Version table:
     5:24.0.5-1~ubuntu24.04~lunar 500
        500 https://download.docker.com/linux/ubuntu lunar/stable amd64 Packages

If the “Candidate” line points to the correct version and the URL includes https://download.docker.com, you’re good to go!

# Install Docker Engine, containerd, and Docker Compose:
sudo apt install docker-ce docker-ce-cli containerd.io docker-compose-plugin

# Check Docker status to ensure it's running
sudo systemctl status docker

Expected Output: You should see a status message similar to this:

● docker.service - Docker Application Container Engine
     Loaded: loaded (/lib/systemd/system/docker.service; enabled; vendor preset: enabled)
     Active: active (running) since Mon 2024-01-01 12:34:56 PST; 1 weeks 3 days ago
  ...

If it shows “Active: active (running)”, Docker is working as expected.

Step 3: Verify Docker Installation

Run a quick test to make sure Docker is working:

Bash

sudo docker run hello-world

Expected Output:

You should see a series of messages, ending with:

Hello from Docker!
This message shows that your installation appears to be working correctly.
...

Step 4: Manage Docker as a Non-Root User (Recommended)

For convenience and security, add your user to the docker group:

sudo usermod -aG docker $USER

Expected Output: No output, but after logging out and back in, you should be able to run Docker commands without sudo.

Step 5: Using Docker

We’ll focus on keeping things isolated, so no port opening is needed. You’ll use tools like:

SSH Tunneling: Securely access applications inside containers.
Docker Volumes: Share files between your VPS and containers.
Docker Networks: Create private networks for your containers to communicate.

Example: Running a Container and Accessing it via SSH Tunnel

# Run a container in detached mode:
docker run -d --name my-container ubuntu 
# Expected output: Unique container ID (e.g., a62079e23c71)

# Create an SSH tunnel (assuming the app in the container is listening on port 80):
ssh -L 8080:localhost:80 user@your_vps_ip

Now, visit http://localhost:8080 in your web browser to access the application inside the container!

Next Steps

Explore Docker Compose to manage multi-container applications.
Learn about Docker volumes for persistent storage.
Dive into Docker networking to create isolated networks.

Let me know if you have any questions. Happy Dockering!