Reference Guide

946 | Virtual LANs (VLAN)
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Assigning an IP address to a VLAN
VLANs are a Layer 2 feature. For two physical interfaces on different VLANs to communicate, you must
assign an IP address to the VLANs to route traffic between the two interfaces.
The
shutdown command in INTERFACE mode does not affect Layer 2 traffic on the interface; the
shutdown command only prevents Layer 3 traffic from traversing over the interface.
To assign an IP address, use the following command in INTERFACE mode:
In Dell networking OS, VLANs and other logical interfaces can be placed in Layer 3 mode to receive and
send routed traffic. For details, see Bulk Configuration
.
Enabling 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. Dell networking OS 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.
Note: An IP address cannot be assigned to the Default VLAN, which, by default, is VLAN 1. To assign
another VLAN ID to the Default VLAN, use the default vlan-id vlan-id command.
Command Syntax Command Mode Purpose
ip address ip-address mask [secondary] INTERFACE Configure an IP address and mask on the interface.
• ip-address mask — Enter an address in
dotted-decimal format (A.B.C.D) and the mask
must be in slash format (/24).
• secondary — This is the interface’s backup IP
address. You can configure up to eight secondary
IP addresses.
Task Command Syntax Command Mode
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).
CONFIGURATION