Google Interview Question

How does the BDR get elected in OSPF?

Interview Answers

Anonymous

Sep 9, 2014

The DR is selected with the router having the highest priority, but because all the routers have a priority of 1 out of the box, the hight Router ID wins, so the second highest router ID become the BDR.

2

Anonymous

Mar 29, 2020

Highest Router-ID becomes DR and the 2nd highest Router-ID becomes BDR in OSPF. It is a priority which elect DR primarily (by default 1 on all). If that matches on all due to its default nature, it will go to Highest IP address of the router loopback interface first and later to the other interface if needed.