Executing a Custom Script to Add Text to Files on Multiple Hosts

Module 5: Ansible Assignment - 2

Tasks To Be Performed:

1. Create a script which can add text “This text has been added by custom script” to /tmp.1.txt
2. Run this script using Ansible on all the hosts

Using the same setup from Assignment 1 – Ansible

EC2 instances

Ansible Control Machine 10.0.1.223 Slave1 10.0.1.65 Slave2 10.0.1.233

Step 1: Write My Custom Script §

I create a script on my Ansible control machine that will append text to a file. I name this script add_text.sh and write the following lines into it:

#!/bin/bash 
echo "This text has been added by custom script" >> /tmp/1.txt

I then make the script executable by running:

chmod +x add_text.sh

Step 2: Craft My Ansible Playbook §

I write an Ansible playbook that will distribute and execute this script on all my managed nodes (hosts). I name the playbook run_script.yml (location, same working directory as add_text.sh) and ensure it contains the following tasks:

---
- hosts: all
  become: yes
  tasks:
    - name: Copy my script to the remote hosts
      copy:
        src: /add_text.sh
        dest: /tmp/add_text.sh
        mode: '0755'
 
    - name: Execute my script
      command: /tmp/add_text.sh

Step 3: Run My Playbook §

I execute my playbook using the following command:

ansible-playbook run_script.yml -i inventory.ini

This command tells Ansible to run my playbook on all the hosts listed in my inventory, copying my script to each one and then executing it, thereby appending the text to /tmp/1.txt on each host.

Step 4: Verify the Changes §

I verify that my script ran successfully on all hosts by checking the content of /tmp/1.txt. If needed, I can do this with another Ansible command:

ansible all -m shell -a 'cat /tmp/1.txt' -i inventory.ini

This command connects to all the hosts in my inventory and outputs the contents of /tmp/1.txt, allowing me to ensure that “This text has been added by custom script” has been appended successfully.

Success