> ## 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 Setup and Install Docker > Learn to install and set up Docker on an Ubuntu VM for modern application deployment. In this lesson, you'll learn how to install and get started with Docker—a powerful containerization platform essential for modern application deployment. We'll walk you through setting up Docker on a supported system, using an Ubuntu VM as our example. Open your browser and navigate to [docs.docker.com](https://docs.docker.com). Click on the "Get Docker" button to access the Docker Engine Community Edition page, which is the free version featured in this guide. ![The image shows the Docker Documentation webpage, offering resources and guides for using Docker, a platform for running applications in containers.](https://kodekloud.com/kk-media/image/upload/v1752874162/notes-assets/images/Docker-Training-Course-for-the-Absolute-Beginner-Demo-Setup-and-Install-Docker/frame_20.jpg) From the left-hand menu, select your system type. For this demonstration, choose Linux, then select your Ubuntu flavor (such as Disco, Cosmic, Bionic, or Sanyo). Make sure to review the prerequisites confirming that your Ubuntu system is 64-bit and one of the supported versions. Ensure that your system meets all prerequisites before proceeding with the Docker installation. ## Step 1: Remove Older Docker Versions Before installing Docker, it is crucial to remove any existing Docker packages. Run the following command: ```bash theme={null} sudo apt-get remove docker docker.io docker-engine ``` Since this setup uses Ubuntu Bionic, verify your Ubuntu version by checking the release information: ```bash theme={null} cat /etc/*release* ``` Example output: ```plaintext theme={null} vagrant@ubuntu-bionic:~$ cat /etc/*release* DISTRIB_ID=Ubuntu DISTRIB_RELEASE=18.04 DISTRIB_CODENAME=bionic DISTRIB_DESCRIPTION="Ubuntu 18.04.2 LTS" NAME="Ubuntu" VERSION="18.04.2 LTS (Bionic Beaver)" ID=ubuntu ID_LIKE=debian PRETTY_NAME="Ubuntu 18.04.2 LTS" VERSION_ID="18.04" HOME_URL="https://www.ubuntu.com/" SUPPORT_URL="https://help.ubuntu.com/" BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/" PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy" VERSION_CODENAME=bionic UBUNTU_CODENAME=bionic vagrant@ubuntu-bionic:~$ ``` Also, remove any older versions to ensure a clean installation: ```bash theme={null} sudo apt-get remove docker docker-engine docker.io containerd runc ``` ## Step 2: Install Docker There are two primary methods to install Docker: using the package manager or the convenience installation script. ### Option 1: Using the Package Manager 1. **Update the Repository and Install Prerequisites**\ Update your package list and install necessary packages: ```bash theme={null} sudo apt-get update sudo apt-get install \ apt-transport-https \ ca-certificates \ curl \ gnupg-agent \ software-properties-common ``` 2. **Add Docker’s Official GPG Key**\ Add the GPG key for Docker: ```bash theme={null} curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add - ``` 3. **Verify the GPG Key Fingerprint**\ Run the following command and ensure the output matches: ```bash theme={null} sudo apt-key fingerprint 0EBFCD88 ``` The expected output should look like: ```plaintext theme={null} pub rsa4096 2017-02-22 [SCEA] 9DC8 5822 9FC7 DD38 854A E2D8 8D81 803C 0EBF CD88 uid [unknown] Docker Release (CE deb) ``` ### Option 2: Using the Convenience Installation Script If you prefer a simpler method, use Docker's convenience script: ```bash theme={null} curl -fsSL https://get.docker.com -o get-docker.sh sudo sh get-docker.sh ``` After executing the script, you can verify its presence: ```bash theme={null} ls get-docker.sh ``` ## Step 3: Verify Docker Installation After installation, check Docker’s version to confirm the installation: ```bash theme={null} sudo docker version ``` A typical output showing Docker version 19.03.1 might appear as follows: ```plaintext theme={null} vagrant@ubuntu-bionic:~$ sudo docker version Client: Docker Engine - Community Version: 19.03.1 API version: 1.40 Go version: go1.12.5 Git commit: 74ble89 Built: Thu Jul 25 21:21:05 2019 OS/Arch: linux/amd64 Experimental: false Server: Docker Engine - Community Engine: Version: 19.03.1 API version: 1.40 (minimum version 1.12) Go version: go1.12.5 Git commit: 74ble89 Built: Thu Jul 25 21:19:41 2019 OS/Arch: linux/amd64 Experimental: false containerd: Version: 1.2.6 GitCommit: 894b81a4b802e4eb2a91d1ce216b8817763c29fb runc: Version: 1.0.0-rc8 GitCommit: 425e105d5a03fabd737a126ad93d62a9eeede87f docker-init: Version: 0.18.0 GitCommit: fec3683 vagrant@ubuntu-bionic:~$ ``` ## Step 4: Run a Docker Container To confirm Docker is running correctly, try launching a simple container. Docker Hub offers a variety of images; in this guide, we'll use the fun "whalesay" image. 1. **Run the Initial Container Command** ```bash theme={null} docker run docker/whalesay cowsay boo ``` Expected output: ```plaintext theme={null} _______ < boo > ------- \ ^__^ \ (oo)\_______ (__)\ )\/\ ||----w | || || ``` 2. **Modify the Command with Sudo and Change the Message** ```bash theme={null} sudo docker run docker/whalesay cowsay Hello-World! ``` When executed, Docker pulls the whale image from Docker Hub and displays a message: ```plaintext theme={null} vagrant@ubuntu-bionic:~$ sudo docker run docker/whalesay cowsay Hello-World! Unable to find image 'docker/whalesay:latest' locally latest: Pulling from docker/whalesay [DEPRECATION NOTICE] registry v2 schema1 support will be removed in an upcoming release. Please contact admins of the docker.io registry NOW to avoid future disruption. e190868d6f3f: Pull complete 909cd34c6fd7: Pull complete 0b9fbabab7c1: Pull complete a3ed95caeb02: Pull complete 0bf65475aba: Pull complete c57b6bcc83e3: Pull complete 897f867892ef: Pull complete 8eed3712d2cf: Pull complete Digest: sha256:178598e51a26abbc958b8a2e48825c90bc22e641de3d31e18aaf55f3258ba93b Status: Downloaded newer image for docker/whalesay:latest __________ < Hello-World! > ---------- \ ^__^ \ (oo)\_______ (__)\ )\/\ ||----w | || || vagrant@ubuntu-bionic:~$ ``` ![The image shows the Docker Hub webpage featuring official images like NGINX, MongoDB, Alpine, Node.js, Redis, and others, each with over 10 million downloads.](https://kodekloud.com/kk-media/image/upload/v1752874163/notes-assets/images/Docker-Training-Course-for-the-Absolute-Beginner-Demo-Setup-and-Install-Docker/frame_170.jpg) ![The image shows the Docker Hub website with a search bar suggesting results for "whalesay" and options to sign up or browse popular images.](https://kodekloud.com/kk-media/image/upload/v1752874164/notes-assets/images/Docker-Training-Course-for-the-Absolute-Beginner-Demo-Setup-and-Install-Docker/frame_180.jpg) While this guide provides an overview of setting up Docker, hands-on labs are available for those who want to experiment and gain further practical experience. ## Conclusion This demonstration has provided a comprehensive guide to installing Docker on an Ubuntu system, from removing previous installations to launching your first container. With Docker now installed, you can begin exploring containerized application deployments and enjoy the benefits of modern development workflows. Happy containerizing!