Network Automation Scripting

Network Automation and Scripting

Automating network device configuration, management, and operations — from Python/Ansible scripts through NetOps/CI/CD pipelines and infrastructure-as-code for networking.

When to Use

• Configuring and managing many network devices
• Automating repetitive network tasks (backups, upgrades, ACL changes)
• Implementing network infrastructure-as-code
• Reducing human error in network changes
• Building NetOps CI/CD pipelines

Automation Patterns

NETWORK_AUTOMATION_PATTERNS = {
    'config_push': 'Push configuration to devices via SSH/API (Netmiko, NAPALM)',
    'config_template': 'Use Jinja2 templates with variables for device configs',
    'state_drift': 'Detect config drift between intended and actual device state',
    'crawl_walk_run': 'Test on 1 device → subset → full rollout',
    'backup_before_change': 'Always backup running config before applying changes',
}

class NetAuto:
    """Automate network device interactions."""
    
    @staticmethod
    def backup_configs(devices: List[Dict], backup_dir: str) -> List[str]:
        """Backup running configs from all devices."""
        from netmiko import ConnectHandler
        results = []
        for device in devices:
            try:
                conn = ConnectHandler(**device)
                config = conn.send_command('show running-config')
                hostname = device.get('host', 'unknown')
                path = f"{backup_dir}/{hostname}_{datetime.now():%Y%m%d}.cfg"
                with open(path, 'w') as f: f.write(config)
                results.append(f"✓ {hostname}: backed up")
                conn.disconnect()
            except Exception as e:
                results.append(f"✗ {device.get('host')}: {e}")
        return results

Common Pitfalls

1. No backup before changes — critical failure without rollback path
2. Unhandled edge cases — device OS differences break scripts; test on each platform
3. Bulk push without validation — pushing to 100 devices without pre/post checks
4. No change management — automated changes bypassing approval processes
5. Credential management — hardcoded credentials in scripts; use vault/secrets

Verification Checklist

• Pre-change backup of all target devices
• Config templates version-controlled (Git)
• Dry-run mode for validation before applying
• Change management process integrated (ticket, approval)
• Rollback plan for each automation run
• Post-change verification (are changes actually applied?)
• Credentials stored in secrets manager (not scripts)