Network ports on an industrial switch can be disabled using either command-line interface (CLI) commands or graphical management tools, depending on the switch model and vendor.

CLI Method (Common for Cisco and Similar Switches)

1. Access the switch CLI via console, SSH, or Telnet.
2. Enter privileged mode:

   CodeCopySwitch> enable

3. Enter global configuration mode:

   CodeCopySwitch# configure terminal

4. Select the port or range of ports to disable:

   CodeCopySwitch(config)# interface fa0/1 Or for multiple ports:

   CodeCopySwitch(config)# interface range fa0/1 - 12

5. Disable the port(s):

   CodeCopySwitch(config-if)# shutdown

6. To re-enable a port later:

   CodeCopySwitch(config-if)# no shutdown

This method is effective for most Cisco Catalyst switches and other CLI-managed industrial switches, enhancing security by preventing unauthorized access on unused ports .

GUI-Based Method (Common for Aruba and Other Managed Switches)

1. Log in to the switch management interface.
2. Navigate to Configuration > Ports > Ports.
3. Select the switch and the ports you want to disable.
4. If a port is part of a configuration (VLAN, LAG, ACL, port mirror, or tunnel), remove it from that configuration first.
5. Use the Actions > Enable/Disable option to disable the selected ports.
6. A success message confirms the ports are disabled .

Disabling Services and TCP/UDP Ports

For additional security, you can disable unused services and TCP/UDP ports:

• Disable unnecessary protocols such as RIP, Telnet, FTP.
• If TCP/UDP ports cannot be disabled directly, use access control lists (ACLs) to block traffic on those ports.
• This approach follows the minimum authorization principle, ensuring only required services are active .

Best Practices

• Document which ports are disabled to avoid accidental disruption.
• Regularly review port usage and re-enable ports only when necessary.
• Combine port shutdown with port security features (MAC address filtering, VLAN assignment) for enhanced protection.
• For switches that support SNMP, configure trap notifications to monitor port status changes . By following these methods, you can effectively disable unused or unnecessary network ports on industrial switches, improving network security and reducing the risk of unauthorized access.