> ## Documentation Index
> Fetch the complete documentation index at: https://notes.kodekloud.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Demo Docker Engine Setup Ubuntu

> This guide explains how to install and configure Docker Engine on an Ubuntu host for running containers.

In this step-by-step guide, you’ll learn how to install and configure the Docker Engine on an Ubuntu host. By the end of this tutorial, your Ubuntu VM will be ready to run containers and support your Docker-based workflows.

## Prerequisites

* A machine running **Ubuntu 16.04** or newer (this example uses **Ubuntu 18.04 “Bionic Beaver”** on `x86_64`).
* A user account with `sudo` privileges.

```bash theme={null}
ubuntu@dockerubuntu:~$ cat /etc/lsb-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=18.04
DISTRIB_CODENAME=bionic
DISTRIB_DESCRIPTION="Ubuntu 18.04.5 LTS"
ubuntu@dockerubuntu:~$ uname -m
x86_64
```

<Callout icon="lightbulb" color="#1CB2FE">
  Make sure your system is up to date before proceeding. Run `sudo apt-get update && sudo apt-get upgrade` if you haven’t recently updated your packages.
</Callout>

## 1. Remove Old Docker Versions

If you have any legacy Docker packages installed, remove them to avoid conflicts:

```bash theme={null}
sudo apt-get remove docker docker-engine docker.io containerd runc
```

## 2. Install Required Packages

Docker’s repository requires HTTPS transport, certificate management, and command-line tools. Update the package index and install these dependencies:

```bash theme={null}
sudo apt-get update
sudo apt-get install \
  apt-transport-https \
  ca-certificates \
  curl \
  gnupg-agent \
  software-properties-common
```

### Prerequisite Packages

| Package                    | Purpose                                     |
| -------------------------- | ------------------------------------------- |
| apt-transport-https        | Allows `apt` to use repositories over HTTPS |
| ca-certificates            | Provides SSL certificates for HTTPS         |
| curl                       | Downloads files from the command line       |
| gnupg-agent                | Manages OpenPGP keys                        |
| software-properties-common | Adds and manages `apt` repositories         |

## 3. Add Docker’s Official GPG Key

Import Docker’s GPG key to verify package signatures:

```bash theme={null}
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -
```

Verify the fingerprint to ensure integrity:

```bash theme={null}
sudo apt-key fingerprint 0EBFCD88
```

<Callout icon="triangle-alert" color="#FF6B6B">
  If the fingerprint does not match `9DC8 5822 9FC7 DD38 854A E2D8 8D81 803C 0EBF CD88`, do **not** continue. Verify your network and retry the key import.
</Callout>

## 4. Set Up the Docker APT Repository

Add Docker’s stable repository to your system:

```bash theme={null}
sudo add-apt-repository \
  "deb [arch=amd64] https://download.docker.com/linux/ubuntu \
  $(lsb_release -cs) \
  stable"
```

## 5. Install Docker Engine

Refresh the package index and install Docker Engine, CLI, and containerd:

```bash theme={null}
sudo apt-get update
sudo apt-get install docker-ce docker-ce-cli containerd.io
```

## 6. Verify the Installation

1. List installed Docker packages:

   ```bash theme={null}
   dpkg -l | grep -i docker
   ```

2. Check that the Docker service is active and enabled at boot:

   ```bash theme={null}
   sudo systemctl status docker
   ```

## 7. View Docker Version and System Information

* Display the Docker client version:

  ```bash theme={null}
  docker --version
  ```

* Show detailed version information for both client and server:

  ```bash theme={null}
  docker version
  ```

* Inspect system-wide Docker details (containers, images, drivers, plugins):

  ```bash theme={null}
  docker info
  ```

Congratulations! You now have **Docker Engine** installed and running on your Ubuntu host. Use this environment to build, ship, and run containerized applications.

## Links and References

* [Docker Engine Documentation](https://docs.docker.com/engine/)
* [Ubuntu Official Site](https://ubuntu.com/)
* [Docker Installation Tutorials](https://docs.docker.com/get-started/)

<CardGroup>
  <Card title="Watch Video" icon="video" cta="Learn more" href="https://learn.kodekloud.com/user/courses/docker-certified-associate-exam-course/module/871494af-49f8-42e9-95e9-cb0df80c2b21/lesson/9149c8c1-70ed-4fcd-a0f3-676a69cc4738" />
</CardGroup>