3com S7906E 安装指导

 

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The VRRP load balancing mode is based on the VRRP standard protocol mode, so mechanisms, such 

as master election, preemption, and tracking functions, in the standard protocol mode are also 

supported in the load balancing mode. Besides, VRRP load balancing mode has some new 

mechanisms, which are introduced in the following parts. 

 

When VRRP works in the load balancing mode, the master allocates virtual MAC addresses to routers 

in the VRRP group and replies the ARP requests (for the IPv4 network) or ND requests (for the IPv6 

network) from different hosts by allocating different virtual MAC addresses to the hosts. The backup 

routers, however, do not reply the ARP requests (for the IPv4 network) or ND requests (for the IPv6 

network) from the hosts. 

Figure 1-7 Allocating virtual MAC addresses 

 

 

 

As shown in 

, the virtual IP address of the VRRP group is 10.1.1.1/24; Router A is the master; 

Router B and Router C are the backups. Router A allocates different virtual MAC addresses to Routers 

A, B and C. 

Host A, Host B, and Host C send ARP requests to obtain the MAC address corresponding to the 

gateway with the virtual IP address 10.1.1.1. The master (Router A) replies ARP requests of the hosts 

with different virtual MAC addresses. 

z 

The MAC address obtained by Host A is the virtual MAC address of Router A, that is, Host A takes 

the virtual MAC address of Router A as the MAC address of the gateway, and thus to ensure that 

the packets from Host A are forwarded by Router A.