What is the purpose of Priority Delta in VRRP?

What is the purpose of Priority Delta in VRRP?
A . When a box is up, Effective Priority = Priority + Priority Delta
B . When an Interface is up, Effective Priority = Priority + Priority Delta
C . When an Interface fail, Effective Priority = Priority C Priority Delta
D . When a box fail, Effective Priority = Priority C Priority Delta

Answer: C

Explanation:

Each instance of VRRP running on a supported interface may monitor the link state of other interfaces. The monitored interfaces do not have to be running VRRP. If a monitored interface loses its link state, then VRRP will decrement its priority over a VRID by the specified delta value and then will send out a new VRRP HELLO packet. If the new effective priority is less than the priority a backup platform has, then the backup platform will beging to send out its own HELLO packet. Once the master sees this packet with a priority greater than its own, then it releases the VIP.

Reference: https://supportcenter.checkpoint.com/supportcenter/portal?

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