Brocade FastIron Ethernet Switch Layer 3 Routing Configuration Guide - Manual (Page 593)

FIGURE 37 Switch 1 and Switch 2 are configured to provide dual redundant network access for the host
In this example, Switch 1 and Switch 2 use VRRP-E to load share as well as provide redundancy to the
hosts. The load sharing is accomplished by creating two VRRP-E groups. Each group has its own
virtual IP addresses. Half of the clients point to VRID 1's virtual IP address as their default gateway and
the other half point to VRID 2's virtual IP address as their default gateway. This organization enables
some of the outbound Internet traffic to go through Switch 1 and the rest to go through Switch 2.
Switch 1 is the Master router for VRID 1 (backup priority = 110) and Switch 2 is the Backup router for
VRID 1 (backup priority = 100). Switch 1 and Switch 2 both track the uplinks to the Internet. If an uplink
failure occurs on Switch 1, its backup priority is decremented by 20 (track priority = 20), so that all traffic
destined to the Internet is sent through Switch 2 instead.
Similarly, Switch 2 is the Master router for VRID 2 (backup priority = 110) and Switch 1 is the Backup
router for VRID 2 (backup priority = 100). Switch 1 and Switch 2 are both tracking the uplinks to the
Internet. If an uplink failure occurs on Switch 2, its backup priority is decremented by 20 (track priority =
20), so that all traffic destined to the Internet is sent through Switch 1 instead.
ARP behavior with VRRP-E
In the VRRP-E implementation, the source MAC address of the gratuitous Address Resolution Protocol
(ARP) request sent by the VRRP-E Master router is the VRRP-E virtual MAC address. When the router
(either the Master or Backup router) sends an ARP request or reply packet, the sender’s MAC address
becomes the MAC address of the interface on the router. When an ARP request packet for the virtual
router IP address is received by the Backup router, it is forwarded to the Master router to resolve the
ARP request. Only the Master router answers the ARP request for the virtual router IP address.
ARP behavior with VRRP-E
FastIron Ethernet Switch Layer 3 Routing Configuration Guide 593
53-1003087-04