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.

Configuration limitations and feature limitations for IP Follow on a virtual routing interface

  • When configuring IP Follow, the primary virtual routing interface should not have ACL or DoS Protection configured. It is recommended that you create a dummy virtual routing interface as the primary and use the IP-follow virtual routing interface for the network.
  • Global Policy Based Routing is not supported when IP Follow is configured.
  • IPv6 is not supported with IP Follow.
  • FastIron devices support IP Follow with OSPF and VRRP protocols only.

Configuration syntax for IP Follow on a virtual routing interface

Configure IP Follow by entering 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 ve 1
device(config-vlan-2)# interface ve 1
device(config-vif-1)# ip address 10.10.2.1/24
device(config-vif-1)# interface ve 2
device(config-vif-2)# ip follow ve 1
device(config-vif-2)# interface ve 3
device(config-vif-3)# ip follow ve 1

Syntax:[no] ip follow ve number

For number, enter the ID of the virtual routing interface.

Use the no form of the command to disable the configuration.

Virtual routing interface 2 and 3 do not have their own IP subnet addresses, but share the IP address of virtual routing interface 1.

Parent topic: Configuring IP addresses