Brocade FastIron Ethernet Switch Layer 3 Routing Configuration Guide - Manual (Page 40)

The num parameter specifies the virtual interface number. You can specify from 1 to the maximum
number of virtual interfaces supported on the device. To display the maximum number of virtual
interfaces supported on the device, enter the show default values command. The maximum is listed
in the System Parameters section, in the Current column of the virtual-interface row.
Assigning an IP address to a virtual interface
A virtual interface is a logical port associated with a Layer 3 Virtual LAN (VLAN) configured on a Layer
3 switch. You can configure routing parameters on the virtual interface to enable the Layer 3 switch to
route protocol traffic from one Layer 3 VLAN to the other, without using an external router.
6
You can configure IP routing interface parameters on a virtual interface. This section describes how to
configure an IP address on a virtual interface. Other sections in this chapter that describe how to
configure interface parameters also apply to virtual interfaces.
NOTE
The Layer 3 switch uses the lowest MAC address on the device (the MAC address of port 1 or 1/1) as
the MAC address for all ports within all virtual interfaces you configure on the device.
To add a virtual interface to a VLAN and configure an IP address on the interface, enter commands
such as the following.
device(config)# vlan 2 name IP-Subnet_10.1.2.0/24
device(config-vlan-2)# untag ethernet 1 to 4
device(config-vlan-2)# router-interface ve1
device(config-vlan-2)# interface ve1
device(config-vif-1)# ip address 10.1.2.1/24
The first two commands in this example create a Layer 3 protocol-based VLAN name "IP-
Subnet_10.1.2.0/24" and add a range of untagged ports to the VLAN. The router-interface command
creates virtual interface 1 as the routing interface for the VLAN.
Syntax: router-interface venum
The num variable specifies the virtual interface number. You can enter a number from 1 through 4095.
When configuring virtual routing interfaces on a device, you can specify a number from 1 through
4095. However, the total number of virtual routing interfaces that are configured must not exceed the
system-max limit of 512. For more information on the number of virtual routing interfaces supported,
refer to "Allocating memory for more VLANs or virtual routing interfaces" section in the FastIron
Ethernet Switch Platform and Layer 2 Switching Configuration Guide.
The last two commands change to the interface configuration level for the virtual interface and assign
an IP address to the interface.
Syntax: interface venum
Configuring IP follow on a virtual routing interface
IP Follow allows multiple virtual routing interfaces to share the same IP address. With this feature, one
virtual routing interface is configured with an IP address, while the other virtual routing interfaces are
configured to use that IP address, thus, they "follow" the virtual routing interface that has the IP
address. This feature is helpful in conserving IP address space.
6 The Brocade feature that allows routing between VLANs within the same device, without the need for external routers,
is called Integrated Switch Routing (ISR).
Assigning an IP address to a virtual interface
40 FastIron Ethernet Switch Layer 3 Routing Configuration Guide
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