How does OSPF determine DR and BDR?
Two rules are used to elect a DR and BDR: router with the highest OSPF priority will become a DR. if there is a tie, a router with the highest router ID wins the election. The router with the second highest OSPF priority or router ID will become a BDR.
What are the roles of OSPF DR and BDR?
Within OSPF, the role of the Designated Router (DR) and a Backup Designated Router (BDR) is to act as a central point for exchanging of OSPF information between multiple routers on the same, multiaccess broadcast network segment. This significantly reduces the amount of OSPF routing updates sent across the network.
What is the LSDB in OSPF?
When OSPF basic topology is used, all the routers in the AS function as peers. Each router communicates routing information with each other one, and each maintains a copy of the key OSPF data structure: the link-state database (LSDB). The LSDB is essentially a computerized representation of the topology of the autonomous system.
What is the use of process ID in OSPF?
It is used to create or modify an existing OSPF routing process and enters the user into OSPF router configuration mode. When configuring OSPF, process-id is used as an identifier of the local OSPF process; different OSPF process IDs would be used on the same router if multiple independent OSPF processes were being run on the same device.
What does the OSPF process ID actually do?
The process ID is the ID of the OSPF process to which the interface belongs. The process ID is local to the router, and two OSPF neighboring routers can have different OSPF process IDs. Cisco IOS® Software can run multiple OSPF processes on the same router, and the process ID merely distinguishes one process from the another.
What is OSPF interface priority?
Default priority for an OSPF interface is 1. The range is from 0 to 255. 0 means that the interface does not involve in the DR election. Beside above, how does OSPF choose DR and BDR? Two rules are used to elect a DR and BDR: router with the highest OSPF priority will become a DR.