VLAN - Native VLAN best practices

When configuring trunk ports on network switches, there are several best practices concerning the Native VLAN to ensure security and network efficiency:

1. Change the Default Native VLAN: It's recommended to change the native VLAN from the default (often VLAN 1) to a different VLAN. This practice helps to mitigate VLAN hopping attacks, where an attacker can exploit the default VLAN to gain unauthorized access to network resources.

2. Use a Dedicated VLAN for Native VLAN Traffic: Create a VLAN that is used exclusively for native VLAN traffic and doesn't carry any user data. This VLAN should not be assigned to any access ports.

3. Avoid Using Native VLAN on User Ports: Don't use the native VLAN for any user-facing ports. Keeping user data and native VLAN traffic separate enhances security.

4. Tagging Native VLAN Traffic: Although the native VLAN is typically untagged, it can be a good practice to tag it, especially in environments where VLANs span multiple switches. This practice ensures better control and understanding of where traffic is flowing, and can aid in troubleshooting.

5. Consistent Native VLAN Across Trunks: Ensure that the native VLAN is consistent across all trunk ports that interconnect switches. Inconsistent native VLAN configurations can lead to traffic leaks and potential security breaches.

By following these best practices, you can significantly enhance the security and efficiency of your network's trunk configurations.

Note that even if you change the native VLAN, some control protocols still use VLAN 1 to send their control frames

Links

https://networklessons.com/switching/802-1q-native-vlan-cisco-ios-switch