LevelOne GTL-2691 - Manual (Page 639)

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C
ONFIGURING
R
OUTER
R
EDUNDANCY
Router redundancy protocols use a virtual IP address to support a primary
router and multiple backup routers. The backup routers can be configured
to take over the workload if the master router fails, or can also be
configured to share the traffic load. The primary goal of router redundancy
is to allow a host device which has been configured with a fixed gateway to
maintain network connectivity in case the primary gateway goes down.
This switch supports the Virtual Router Redundancy Protocol (VRRP). VRRP
allows you to specify the interface of one of the routers participating in the
virtual group as the address for the master virtual router, or to configure
an arbitrary address for the virtual master router. VRRP then selects the
backup routers based on the specified virtual router priority.
Router redundancy can be set up in any of the following configurations.
These examples use the address of one of the participating routers as the
master router. When the virtual router IP address is not a real address, the
master router is selected based on priority. When the priority is the same
on several competing routers, then the router with the highest IP address
is selected as the master.
Figure 393: Master Virtual Router with Backup Routers
Figure 394: Several Virtual Master Routers Using Backup Routers
Master Router Backup Router
Virtual Router (VR23)
VRIP = 192.168.1.3
VRID 23
IP(R1) = 192.168.1.3
IP(VR23) = 192.168.1.3
VR Priority = 255 VRID 23
IP(R2) = 192.168.1.5
VRIP(VR23) = 192.168.1.3
VR Priority = 100
Master Router
VRID 23
IP(R1) = 192.168.1.3
IP(VR23) = 192.168.1.3
VR Priority = 255
Master Router
VRID 25
IP(R2) = 192.168.2.17
IP(VR25) = 192.168.2.17
VR Priority = 255
Backup Router
VRID 23
IP(R3) = 192.168.1.4
IP(VR23) = 192.168.1.3
VR Priority = 100
VRID 25
IP(R3) = 192.168.2.18
IP(VR23) = 192.168.2.17
VR Priority = 100