Ansible cheatsheet

Ad-hoc commands

Command	Description
`ansible web -m ping`	Test SSH connectivity
`ansible all -m setup`	Gather facts
`ansible web -a "uptime"`	Run shell command
`ansible web -b -m apt -a "name=htop state=present"`	Install package as root
`ansible-inventory --list`	Show resolved inventory
`ansible-playbook site.yml --start-at-task "Install nginx"`	Resume playbook from named task
`ansible-playbook site.yml --start-at-task "Deploy app" -l web01`	Resume from task on one host

Playbooks

ansible-playbook site.yml
ansible-playbook site.yml --check          # dry run
ansible-playbook site.yml --diff             # show file diffs
ansible-playbook site.yml -l web01           # limit to host
ansible-playbook site.yml -e "env=prod"      # extra var
ansible-playbook site.yml --tags deploy
ansible-playbook site.yml --skip-tags test

Inventory snippet (INI)

[web]
web01 ansible_host=10.0.1.10 ansible_user=ubuntu
web02 ansible_host=10.0.1.11

[web:vars]
ansible_ssh_private_key_file=~/.ssh/deploy.pem

Common modules

Module	Purpose
`ansible.builtin.copy`	Copy static file
`ansible.builtin.template`	Render Jinja template
`ansible.builtin.file`	Permissions, symlinks, directories
`ansible.builtin.service`	systemd/service state
`ansible.builtin.aptyum`	Package install
`ansible.builtin.commandshell`	Run commands (prefer specialized modules)
`ansible.builtin.user`	Local user accounts

Handler pattern

  tasks:
    - name: Deploy nginx config
      ansible.builtin.template:
        src: nginx.conf.j2
        dest: /etc/nginx/nginx.conf
      notify: Reload nginx

  handlers:
    - name: Reload nginx
      ansible.builtin.service:
        name: nginx
        state: reloaded

Role layout

roles/myapp/
  tasks/main.yml
  handlers/main.yml
  templates/
  files/
  defaults/main.yml
  vars/main.yml

Galaxy and collections

ansible-galaxy role install geerlingguy.nginx
ansible-galaxy collection install -r requirements.yml
ansible-galaxy role list

Debug and verbosity

ansible-playbook site.yml -vvv
ansible-playbook site.yml --step          # confirm each task
ansible-playbook site.yml --start-at-task "Install nginx"

Pro tips

ansible -m ping all before long playbooks — fix SSH first
Use --check --diff to preview changes safely
Prefer dedicated modules over command for idempotency
Pin Galaxy roles/collections in requirements.yml
serial: or rolling strategy for zero-downtime deploys