Dell Force10 MXL Blade MXL 10/40GbE Switch IO Module Configuration Guide - Page 633

To configure a port so that it can be a member of an untagged and tagged VLANs, follow these steps: Step 1 2 3 4 Task Command Remove any Layer 2 or Layer 3 configurations from the interface. Configure the interface for hybrid mode. portmode hybrid Configure the interface for switchport mode. switchport Add the interface to a tagged or untagged VLAN. [tagged | untagged] Command Mode INTERFACE INTERFACE INTERFACE VLAN INTERFACE Note: You cannot configure an existing switchport or port channel interface for Native VLAN. Interfaces must have no other Layer 2 or Layer 3 configurations when entering the command portmode hybrid or a message similar to Message 1 is displayed. Message 1 Native VLAN Error % Error: Port is in Layer-2 mode Tengig 5/6. Enable Null VLAN as the Default VLAN In a Carrier Ethernet for Metro Service environment, service providers who perform frequent reconfigurations for customers with changing requirements occasionally enable multiple interfaces, each connected to a different customer, before the interfaces are fully configured. This presents a vulnerability because both interfaces are initially placed in the native VLAN (VLAN 1) and for that period customers are able to access each other's networks. FTOS has a null VLAN to eliminate this vulnerability. When you enable the null VLAN, all ports are placed into by it default, so that even if you activate the physical ports of multiple customers, no traffic is allowed to traverse the links until each port is place in another VLAN. To disable the default VLAN, use the following command: Task Command Syntax Disable the default VLAN, so that all ports belong to the Null VLAN until configured as a member of another VLAN. default-vlan disable Default: the default VLAN is enabled (no default-vlan disable). Command Mode CONFIGURATION Virtual LANs (VLAN) | 631