## Modules Reference

Commonly used Ansible modules:

### Core Modules

1. **setup** (Automatically collects system information):
   ```yaml
   - name: Gather system facts
     ansible.builtin.setup:
   ```

2. **debug** (For troubleshooting):
   ```yaml
   - name: Show variable value
     ansible.builtin.debug:
       msg: "{{ some_variable }}"
   ```

3. **copy** (For file transfer):
   ```yaml
   - name: Copy file to remote host
     ansible.builtin.copy:
       src: "local_file.txt"
       dest: "/remote/path/"
   ```

4. **service** (For service management):
   ```yaml
   - name: Restart web service
     ansible.builtin.service:
       name: apache2
       state: restarted
   ```

### Network Modules

5. **ping** (Test connectivity):
   ```yaml
   - name: Test connection to host
     ansible.builtin.ping:
   ```

6. **sshcopy** (Copy files via SSH):
   ```yaml
   - name: Copy file using SSH
     ansible.builtin.sshcopy:
       src: "local_file.txt"
       dest: "user@host:/remote/path/"
   ```

### Best Practices

- Use `ansible-doc` to view module details
- Combine with `when` conditions for targeted execution
- Use `--check` flag to simulate module operations
- Store sensitive data using Ansible Vault

### Troubleshooting

- Use `--verbosity=2` for detailed output
- Check module documentation for parameter requirements
- Use `ansible-playbook --list-tasks` to verify task execution order