Automation

git: change history, undo and a remote repository

A version control system: who changed what in the files, how to get back a working version and exchange changes.

Ansible: inventory, modules and one-off commands

Configures servers over SSH: from an inventory and playbooks it brings machines to a described state, no agent needed.

ansible-playbook: running a playbook

Runs an Ansible playbook on the inventory machines and reports ok, changed, skipping or failed for each task.