1-6z If you configure the preemption delay for a backup, the switch preempts the master if it does notreceive a VRRP advertisement from the master after it waits for a period three times of theadvertisement interval and the period specified by the preemption delay.VRRP Trackingz If an IP address owner exists in a VRRP group, you can configure a priority for the IP addressowner. However your configuration will not take effect and the IP address owner will still be themaster of the VRRP group because the system considers the priority of the IP address owner to be255 always.z If an IP address owner exists in a VRRP group, the interface/port tracking function configured onthe IP address owner cannot take effect.Interface tracking function of the VRRP groupWhen the VLAN interface of the master goes down, if you want the specified backup to become themaster, you can use the interface tracking function. With this function enabled for the VRRP group:z If the tracked VLAN interface of the master goes down, the priority of the switch decreasesautomatically by a specified value.z The decrease of the master priority makes the priority of the backup tracking the interface becomehigher, and thus the backup becomes the new master.Port tracking function of the VRRP groupWhen a physical port of the master goes down, if you want the specified backup to become the master,you can use the port tracking function. With this function enabled for the VRRP group:z If the tracked physical port of the master goes down, the priority of the master decreasesautomatically by a set value.z The decrease of the master priority makes the priority of the backup tracking the port becomehigher, and thus the backup becomes the new master.Operation Procedure of VRRPz With VRRP enabled, the switches determine their respective roles in a VRRP group by priority. Theswitch with the highest priority acts as the master, which will forward packets to outside networks,and the switches with lower priorities act as backups. The master sends VRRP advertisementsperiodically to notify that it is operating normally.z When a backup receives a VRRP advertisement, it compares its own priority with that in theadvertisement. If its priority is lower, it remains as a backup. Otherwise, it becomes the master.z A backup starts the advertisement interval timer after it receives the advertisement to wait for thenext one from the master. If the backup does not receive VRRP advertisements from the masterafter the timer expires, it considers that the master fails and starts the election process to elect anew master for forwarding packets.
