Concept Guide

By default, VLAN 1 is the Default VLAN. To change that designation, use the default vlan-id command in CONFIGURATION mode.
You cannot delete the Default VLAN.
NOTE: You cannot assign an IP address to the Default VLAN. To assign an IP address to a VLAN that is currently the Default
VLAN, create another VLAN and assign it to be the Default VLAN. For more information about assigning IP addresses, refer to
Assigning an IP Address to a VLAN.
• Untagged interfaces must be part of a VLAN. To remove an untagged interface from the Default VLAN, create another VLAN and place
the interface into that VLAN. Alternatively, use the no switchport command, and Dell Networking OS removes the interface from
the Default VLAN.
• A tagged interface requires an additional step to remove it from Layer 2 mode. Because tagged interfaces can belong to multiple
VLANs, remove the tagged interface from all VLANs using the no tagged interface command. Only after the interface is
untagged and a member of the Default VLAN can you use the no switchport command to remove the interface from Layer 2
mode. For more information, refer to VLANs and Port Tagging.
Example of Conguring an Interface for Layer 2 Belonging to the Default VLAN
Dell(conf)#int tengig 3/2
Dell(conf-if)#no shut
Dell(conf-if)#switchport
Dell(conf-if)#show config
!
interface Tengigabitethernet 3/2
no ip address
switchport
no shutdown
Dell(conf-if)#end
Dell#show vlan
Codes: * - Default VLAN, G - GVRP VLANs
NUM Status Q Ports
* 1 Active U Tengig 3/2
2 Active T Po1(So 0/0-1)
T Tengig 3/0
Dell#
Port-Based VLANs
Port-based VLANs are a broadcast domain dened by dierent ports or interfaces. In the Dell Networking OS, a port-based VLAN can
contain interfaces from dierent line cards within the chassis. Dell Networking OS supports 4094 port-based VLANs.
Port-based VLANs oer increased security for trac, conserve bandwidth, and allow switch segmentation. Interfaces in dierent VLANs
do not communicate with each other, adding some security to the trac on those interfaces. Dierent VLANs can communicate between
each other by means of IP routing. Because trac is only broadcast or ooded to the interfaces within a VLAN, the VLAN conserves
bandwidth. Finally, you can have multiple VLANs congured on one switch, thus segmenting the device.
Interfaces within a port-based VLAN must be in Layer 2 mode and can be tagged or untagged in the VLAN ID.
VLANs and Port Tagging
To add an interface to a VLAN, the interface must be in Layer 2 mode. After you place an interface in Layer 2 mode, the interface is
automatically placed in the Default VLAN.
The Dell Networking OS supports IEEE 802.1Q tagging at the interface level to lter trac. When you enable tagging, a tag header is added
to the frame after the destination and source MAC addresses. That information is preserved as the frame moves through the network. The
following example shows the structure of a frame with a tag header. The VLAN ID is inserted in the tag header.
914
Virtual LANs (VLANs)