| Configuring Router Redundancy
C
19
HAPTER
Configuring VRRP Groups
C
VRRP G
ONFIGURING
Figure 458: Several Virtual Master Routers Configured for Mutual Backup
and Load Sharing
Router 1
VRID 23 (Master)
IP(R1) = 192.168.1.3
IP(VR23) = 192.168.1.3
VR Priority = 255
VRID 25 (Backup)
IP(R1) = 192.168.1.3
IP(VR25) = 192.168.1.5
VR Priority = 100
LAN Segment A
Hosts (192.168.1.10-99)
Load sharing can be accomplished by assigning a subset of
N
:
OTE
addresses to different host address pools using the DHCP server. (See
"Configuring Address Pools" on page
ROUPS
Use the IP > VRRP pages to configure VRRP. To configure VRRP groups,
select an interface on each router in the group that will participate in the
protocol as the master router or a backup router. To select a specific device
as the master router, set the address of this interface as the virtual router
address for the group. Now set the same virtual address and a priority on
the backup routers, and configure an authentication string. You can also
enable the preempt feature which allows a router to take over as the
master router when it comes on line if it has a higher priority than the
currently active master router.
CLI R
EFERENCES
"VRRP Commands" on page 1713
◆
C
U
OMMAND
SAGE
Address Assignment –
To designate a specific router as the VRRP master, the IP address
◆
assigned to the virtual router must already be configured on the router
that will become the Owner of the group address. In other words, the
IP address for the virtual router exists on one, and only one, router in
the virtual router group, and the network mask for the virtual router
address is derived from the Owner. The Owner will also assume the role
of the Master virtual router in the group.
If a virtual address is assigned to the group which does not exist on any
◆
of the group members, then the master router is selected based on
– 760 –
Router 2
VRID 23 (Backup)
IP(R1) = 192.168.1.5
IP(VR23) = 192.168.1.3
VR Priority = 100
VRID 25 (Master)
IP(R1) = 192.168.1.5
IP(VR25) = 192.168.1.5
VR Priority = 255
LAN Segment B
Hosts (192.168.1.100-250)
726)