trainings/ansible/training/lessons/2-inventory.md

Inventory

Until now, you only used ansible to manage localhost.

But ansible can be used to manage multiple systems that you have in your infrastructure. To do so, we must tell ansible which servers compose our infrastructure. This is done thanks to an inventory file. The default inventory file for ansible is located in /etc/ansible/hosts.

For now, your inventory is empty, so you can create one:

mkdir -p /etc/ansible/
touch /etc/ansible/hosts

With an empty inventory like that, ansible only knows about localhost.

Demo server

Add a server in your inventory

Add the following line at the end of your inventory:

demo ansible_username=root ansible_password=root ansible_connection=ssh ansible_host=127.0.0.2 ansible_port=2222 ansible_python_interpreter=/usr/bin/python3

This line adds our server named demo in ansible inventory. It also configure ansible to connect with login root, password root on port 2222. The server IP address is 127.0.0.2 which sound weird, but that's because it's a docker container running locally (for the demo). Finally, we tell ansible to use python3 interpreter (default is python, but it's not available in the demo server).

Check if running

Try to connect on your demo machine, to see if it's running:

ssh -p 2222 root@127.0.0.2

ping

Now use an ansible ad-hoc module to check if ansible is able to connect to this machine

ansible ...  # complete by yourself / see previous lessons