Which multicast address corresponds to all OSPF DRs/BDRs in IPv6?

The multicast address that corresponds to all OSPF Designated Routers (DRs) and Backup Designated Routers (BDRs) in IPv6 is FF02::6. This address is specifically used by OSPFv3, the version of the Open Shortest Path First (OSPF) protocol that is used with IPv6.

In OSPFv3, this multicast address enables routers to send OSPF routing information to all DRs and BDRs on a network segment, which is crucial for efficient routing and minimizing unnecessary traffic on the network. The DRs are responsible for representing the network segment's routing information to OSPF neighbors, and the BDR stands by to take over if the DR fails, ensuring reliability in OSPF operation.

The other provided addresses serve different functions in the IPv6 multicast addressing scheme. For example, FF02::2 is a multicast address used for all routers, while FF02::5 is meant for all OSPF routers. FF02::9 is used for all IS-IS routers. Therefore, FF02::6 is significant specifically for OSPF's DR and BDR roles, establishing it as the correct choice for identifying all OSPF DRs