User's Manual

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Users Manual of GPL-8000
forwards the packets whose destination address is the virtual MAC address of the backup group. When VRRP
detects the invalidity of the main router, the VRRP routers will select one as a new main router to obtain the
MAC and the IP of the backup group.
The VRRP-running main router transmits the Advertise packets based on the Sock Raw multicast, while the
standby routers receive these packets. The standby routers can serve as the main router through their Timer
out mechanism and the Preempt mechanism. You can configure multiple hot standby groups on an interface
to fully use the router.
Currently VRRP supports Ethernet/Fast Ethernet/VLAN protocols, but it does not support the token ring and
the token bus.
VRRP is designated by IETF VRRP working group which is defined in RFC2338.
49.3.1.1 VRRP Application
Line backup
You can back up a link through VRRP.
For example, if a node in a company or in a bank wants to connect the outside network through the VRRP
group, another router will automatically take over the jobs when one router invalidates.
Figure 3-1 VRRP application
49.3.1.2 VRRP Terms
VRRP Virtual Router Redundancy Protocol
VIP
Virtual IP
VMAC
Virtual MAC address
VRRP Router
A router which runs VRRP
Virtual Router
a VRRP group which is viewed by other parts in the network as
a virtual router
IP Address
Owner
A VRRP router that sets a real IP of an interface to VRRP VIP
VirtualRouter
Active router that forwards the data in the current VRRP group