Ansible Playbook for automatic installation and configuration of:

• Docker
• Docker-compose
• Java-openJDK-1.8 on RedHat Enterprise Linux 7

Custom role for installing docker only using official RH EL7 repository - docker-rhel

• ✔ Automatic intallation of requirements
• ✔ Automatic installation of missing packages
• ✔ Automatic update of system packages
• ✔ RedHat EL 7+ compatibility
• ✔ Automatic Docker installation
• ✔ Automatic Docker Compose installation in latest version (from GitHub)

To use the Ansible Playbook for setup of Docker and Docker-compose the following prerequisites must be installed:

• Make sure the Host OS has public IP
• Make sure it is possible to acces via SSH

Having all Prerequisites set up please follow the next steps to configure environment.

git clone https://github.com/bitroniq/ansible-docker-rhel.git

Before Ansible Playbook can be played on target host, some roles from Ansible Galaxy must be installed.

ansible-galaxy install -r requirements.yml

Edit the inventory file with favorite editor:

vim inventory.yml

Replace hostname with the IP address of target host (guest OS):

---
all:
  hosts:
    IP_ADDRESS_OF_GUEST_OS:

On the local host execute the command from the listing below. Ansible will ask for:

• user password: PASSWORD
• sudo password: PASSWORD

ansible-playbook -i inventory.yml site.yml --ask-pass --ask-su-pass -u ec2-user

After few minutes all packages should be installed and the system should be configured accordingly.

Installation logs:

$ ansible-playbook -i inventory.yml site.yml --ask-pass --ask-su-pass -u ec2-user
SSH password:
SUDO password[defaults to SSH password]:

PLAY [all] ****************************************************************************************

TASK [Gathering Facts] ****************************************************************************
ok: [172.16.75.19]

TASK [Update packages] ****************************************************************************
ok: [172.16.75.19]

TASK [Install python for Ansible] *****************************************************************
changed: [172.16.75.19]

TASK [Gathering Facts] ****************************************************************************
ok: [172.16.75.19]

[...]
[...]

PLAY RECAP ****************************************************************************************
172.16.75.19               : ok=36   changed=21   unreachable=0    failed=0

Ansible will take care of adding user ec2-user to group docker. But it is needed to log out and log back in so that your group membership is re-evaluated.

If testing on a virtual machine, it may be necessary to restart the virtual machine for changes to take effect.

On a desktop Linux environment such as X Windows, log out of your session completely and then log back in.

Verify that you can run docker commands without sudo.

$ docker run hello-world

This command downloads a test image and runs it in a container. When the container runs, it prints an informational message and exits.

If you initially ran Docker CLI commands using sudo before adding your user to the docker group, you may see the following error, which indicates that your ~/.docker/ directory was created with incorrect permissions due to the sudo commands.

WARNING: Error loading config file: /home/user/.docker/config.json -
stat /home/user/.docker/config.json: permission denied
To fix this problem, either remove the ~/.docker/ directory (it is recreated automatically, but any custom settings are lost), or change its ownership and permissions using the following commands:
$ sudo chown "$USER":"$USER" /home/"$USER"/.docker -R
$ sudo chmod g+rwx "$HOME/.docker" -R

Information for developers

The repository contains the following files and directories:

.
├ common
│   └ tasks
│       ├ debian.yml
│       ├ main.yml
│       └ redhat.yml
├ docker-rhel
│   ├ defaults
│   │   └ main.yml
│   ├ handlers
│   │   └ main.yml
│   └ tasks
│       ├ docker-compose.yml
│       ├ docker-users.yml
│       ├ main.yml
│       └ setup-RedHat.yml
├ inventory.yml
├ LICENSE
├ README.md
├ requirements.yml
├ site.yml
├ test-nodes
│   ├ docker-centos-7
│   │   └ Dockerfile
│   ├ docker-ubuntu-18.04
│   │   ├ Dockerfile
│   │   ├ initctl_faker
│   │   └ README.md
│   ├ vagrant-multi
│   │   └ Vagrantfile
│   └ vagrant-single
│       └ Vagrantfile
└ tests
    ├ inventory
        ├ test.yml
	    └ vagrant.yml

• common - role for installing basic packages (git, vim, mc)
• docker-rhel - role for installing docker and docker-compose
• inventory.yml - inventory file where the target hosts should be defined
• LICENSE
• README.md - This readme file
• requirements.yml - List of Ansible Galaxy roles
• site.yml - Main Playbook that lists the roles to be played on target host
• test-nodes
  • docker-centos-7 - used for building docker container with CentOS 7 to test the Playbook
  • docker-ubuntu-18.04 - used for building docker container with Ubuntu 18.04 to test the Playbook
  • vagrant-multi - Vagrantfile that will run many different Linux versions to test the Playbook
  • vagrant-single - Vagrantfile that will run single machine
• tests - Playbook that is used by Vagrant to test the playbooks on different Linux versions

site.yml is the main Playbook that contains the list if variables and roles to be played on target host.

First the pre_tasks are played to update packages on target host(s) and to install Python needed by Ansible on both local host and target host.

Ansible will also gather facts about the target host(s):

    - name: Gathering Facts
      setup:

This is needed to determine the target OS version etc.

Then the roles will be played:

 roles:
   # Play role common with base packages
   - role: common

   # Play role docker-rhel to install docker and docker-compose
   - role: docker-rhel
     when: "ansible_os_family == 'RedHat'"

   # Play role geerlingguy.java to install java
   - role: geerlingguy.java
     when: "ansible_os_family == 'RedHat'"
     java_packages:
       - java-1.8.0-openjdk

• common will install the basic packages:
  • name: Ensure git is present
  • name: Ensure vim is present
  • name: Ensure mc is present
• docker-rhel - role to install latest Docker - maintained by the community
• geerlingguy.java - Ansible Galaxy role to install Java - maintained by the community

1. Fork it (https://github.com/bitroniq/ansible-docker-rhel/fork)
2. Create your feature branch (git checkout -b feature/fooBar)
3. Commit your changes (git commit -am 'Add some fooBar')
4. Push to the branch (git push origin feature/fooBar)
5. Create a new Pull Request

• https://galaxy.ansible.com/geerlingguy/java
• https://galaxy.ansible.com/geerlingguy/docker
• https://docs.ansible.com/ansible/latest/user_guide/playbooks_best_practices.html