• Run a playbook:

```

  ansible-playbook playbook.yml
  ```

• Run an ad-hoc command:

```

  ansible <host> -m <module> -a "<arguments>"
  ```

• List available modules:

```

  ansible-doc -l
  ```

• Check if a host is reachable:

```

  ansible <host> -m ping
  ```

• List facts about a host:

```

  ansible <host> -m setup
  ```

• Specify inventory file:

```

  ansible-playbook -i inventory_file playbook.yml
  ```

• Host group example in inventory file:

```

  [web]
  webserver1
  webserver2
  ```

• Dynamic Inventory (AWS example):

```

  ansible-playbook -i aws_ec2.py playbook.yml
  ```

• Simple playbook:

```yaml

1. –
2. name: Install a package

hosts: web

    tasks:
      - name: Install nginx
        ansible.builtin.yum:
          name: nginx
          state: present
  ```

• Playbook with variables:

```yaml

1. –
2. name: Install package with variable

hosts: web

    vars:
      package_name: nginx
    tasks:
      - name: Install nginx
        ansible.builtin.yum:
          name: "{{ package_name }}"
          state: present
  ```

• Playbook with roles:

```yaml

1. –
2. name: Install and configure web server

hosts: web

    roles:
      - webserver
  ```

• Yum (Install package):

```yaml

1. name: Install package

ansible.builtin.yum:

      name: nginx
      state: present
  ```

• Copy (Copy file):

```yaml

1. name: Copy file

ansible.builtin.copy:

      src: /local/path/to/file
      dest: /remote/path/to/file
  ```

• Command (Run a command):

```yaml

1. name: Run a command

ansible.builtin.command: /bin/echo Hello World

  ```

• File (Change file attributes):

```yaml

1. name: Change file permissions

ansible.builtin.file:

      path: /path/to/file
      mode: '0644'
  ```

• Service (Manage services):

```yaml

1. name: Start nginx service

ansible.builtin.service:

      name: nginx
      state: started
  ```

• Define variables in playbook:

```yaml

  vars:
    var_name: value
  ```

• Use variables in tasks:

```yaml

1. name: Install package

ansible.builtin.yum:

      name: "{{ var_name }}"
      state: present
  ```

• Define host variables in inventory:

```

  [web]
  webserver1 ansible_ssh_user=ubuntu
  ```

• Use facts in playbook:

```yaml

1. name: Print host IP

debug:

      var: ansible_default_ipv4.address
  ```

• Loop over items:

```yaml

1. name: Install multiple packages

ansible.builtin.yum:

      name: "{{ item }}"
      state: present
    loop:
      - nginx
      - vim
  ```

• When conditional:

```yaml

1. name: Install nginx if variable is true

ansible.builtin.yum:

      name: nginx
      state: present
    when: install_nginx == true
  ```

• Loop with index:

```yaml

1. name: Print index of items

debug:

      msg: "Item {{ item }} is at index {{ ansible_loop.index }}"
    loop:
      - one
      - two
      - three
  ```

• Define a handler:

```yaml

  handlers:
    - name: Restart nginx
      ansible.builtin.systemd:
        name: nginx
        state: restarted
  ```

• Notify a handler:

```yaml

1. name: Modify nginx config

ansible.builtin.copy:

      src: nginx.conf
      dest: /etc/nginx/nginx.conf
    notify: Restart nginx
  ```

• Create a new encrypted file:

```

  ansible-vault create secret.yml
  ```

• Edit an encrypted file:

```

  ansible-vault edit secret.yml
  ```

• Encrypt an existing file:

```

  ansible-vault encrypt existing_file.yml
  ```

• Decrypt a file:

```

  ansible-vault decrypt secret.yml
  ```

• Run a playbook with vault password:

```

  ansible-playbook --ask-vault-pass playbook.yml
  ```

• Check syntax of a playbook:

```

  ansible-playbook --syntax-check playbook.yml
  ```

• Run playbook in check mode (dry-run):

```

  ansible-playbook --check playbook.yml
  ```

• Run playbook with verbose output:

```

  ansible-playbook -v playbook.yml
  ```

• Display detailed information about a module:

```

  ansible-doc <module_name>
  ```

• [Ansible Documentation](https://docs.ansible.com/)
• [Ansible GitHub Repository](https://github.com/ansible/ansible)