Avaya ERS 8600 series, Руководство по настройке

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For VRID 1, R1 is the master and R2 is the backup. For VRID 2, R2 is the master and R1 is
the backup.
This configuration not only shares the load of the outgoing traffic, but it also provides full
redundancy. If either router fails, the other router assumes responsibility for both addresses.
Figure 12: Virtual Router Redundancy Protocol configuration
When a VRRP router is initialized, if it is the IP address owner, it asserts itself as the master
router with a priority of 255 and it sends a VRRP advertisement. The VRRP router also sends
unsolicited ND Neighbor Advertisements and ND Router Advertisements containing the virtual
router MAC address for each IP address associated with the virtual router. The VRRP router
then transitions to the controlling state.
In the controlling state, the VRRP router functions as the forwarding router for the IP addresses
associated with the virtual router. It responds to ND Neighbor Solicitation and ND Router
Solicitation messages for these IP addresses, forwards packets with a destination MAC
address equal to the virtual router MAC address, and accepts only packets addressed to IP
addresses associated with the virtual router if it is the IP address owner.
If the VRRP router is initialized and the priority is not 255, the router transitions to the backup
state to ensure that all Layer 2 switches in the down path relearn the new origin of the VRRP
MAC addresses.
In the backup state, a VRRP router monitors the availability and state of the master router. It
does not respond to ND Neighbor Solicitation and ND Router Solicitation messages for virtual
router IP addresses and discards packets with a MAC address equal to the virtual router MAC
address. It does not accept packets addressed to IP addresses associated with the virtual
router. If a shutdown occurs, it transitions back to the initialize state. If the master router goes
down, the backup router sends the VRRP advertisement and unsolicited ND Neighbor
Advertisements and ND Router Advertisements described in the preceding paragraphs and
transitions to the controlling state.
IPv6 routing fundamentals
62 Configuration — IPv6 Routing November 2010