Ansible 5 of 9: Playbooks 2 of 2

January 16, 2024

Background

This is a continuation of the prior article

1 of 6. Open Cloud9

2 of 6. Install nginx using ansible (yum and shell modules)

Update cache, install nginx, start nginx, and remove nginx. Check the status after starting to confirm that it started up. Attempt to reach the webserver, to validate that it works. Remove the webserver. Finally, validate the webserver stops working post removal.


ansible all -m yum -a "update_cache=yes name=nginx state=latest" -b
ansible all -m shell -a "systemctl status nginx"
ansible all -m shell -a "systemctl start nginx" -b
ansible all -m shell -a "systemctl status nginx"

3 of 6. Check HTTP to the webserver

You can use the AWS CLI to grab the public IPs. After checking the site via web browser, remove nginx.


aws ec2 describe-instances \
    --query 'Reservations[*].Instances[*].{Instance:InstanceId,Name:Tags[?Key==`Name`]|[0].Value,PublicIP:PublicIpAddress,PrivateIP:PrivateIpAddress,State:State.Name}' \
    --output table

ansible all -m yum -a "name=nginx state=absent" -b
ansible all -m shell -a "systemctl status nginx"

4 of 6. Create a playbook for installing nginx

We would use a playbook, so that if we had to do this repetitive task in the future, we would not have to run a series of commands to install the nginx web service. Create the file install-webserver.yml inside the ansible-tasks folder, then populate it with the below content


pwd
touch install-webserver.yml


- name: Installing & starting ngnix
  hosts: all
  become: yes
  tasks:
    - name: Installing ngnix
      yum:
        update_cache: yes
        name: nginx
        state: latest

    - name: Starting NGINX
      shell: systemctl start nginx

    - name: Enable the NGINX service during boot process
      service:
        name: nginx
        enabled: yes

5 of 6. Install NGINX using ansible playbook.

Make sure to check to validate that the webserver is reachable. Because playbooks are reusable, you could run this exact same playbook at a future time. Imagine if you had a more extensive automation to deploy, and you can easily see how useful it is to leverage a playbook.

ansible-playbook install-webserver.yml
ansible all -m shell -a "systemctl status nginx"

6 of 6. Destroy the environment.

Check the console and validate that the instances were terminated.

terraform destroy


aws ec2 describe-instances \
    --query 'Reservations[*].Instances[*].{Instance:InstanceId,Name:Tags[?Key==`Name`]|[0].Value,PublicIP:PublicIpAddress,PrivateIP:PrivateIpAddress,State:State.Name}' \
    --output table