Specifications

170 ExtremeWare XOS 10.1 Concepts Guide
Virtual Router Redundancy Protocol
physical interface. Each physical interface on each backup router must have a unique IP address. The
virtual router IP address is also used as the default gateway address for each host on the network.
If the master router fails, the backup router assumes forwarding responsibility for traffic addressed to
the virtual router MAC address. However, because the IP address associated with the master router is
not physically located on the backup router, the backup router cannot reply to TCP/IP messages (such
as pings) sent to the virtual router.
Fully-Redundant VRRP Network
You can use two or more VRRP-enabled switches to provide a fully-redundant VRRP configuration on
your network. Figure 29 shows a fully-redundant VRRP configuration.
Figure 29: Fully-redundant VRRP configuration
In Figure 29, switch A is configured as follows:
• IP address 192.168.1.3
• Master router for VRID 1
• Backup router for VRID 2
• MAC address 00-00-5E-00-01-01
Switch B is configured as follows:
• IP address 192.168.1.5
• Master router for VRID 2
• Backup router for VRID 1
• MAC address 00-00-5E-00-01-02
Both virtual routers are simultaneously operational. The traffic load from the four hosts is split between
them. Host 1 and host 2 are configured to use VRID 1 on switch A as their default gateway. Host 3 and
host 4 are configured to use VRID 2 on switch B as their default gateway. In the event that either switch
fails, the backup router configured is standing by to resume normal operation.
EX_069
Default Route
Switch A
Master for virtual IP 192.168.1.3
Master VRID = 1
Backup for virtual IP 192.168.1.5
Backup VRID = 2
MAC address = 00-00-5E-00-01-01
Switch B
Master for virtual IP 192.168.1.5
Master VRID = 2
Backup for virtual IP 192.168.1.3
Backup VRID = 1
MAC address = 00-00-5E-00-01-02
Backup Route