How do I find my OSPF router ID?
If there is no OSPF Router ID configured, the highest IP address on any of the Routers Loopback Interfaces is selected as the OSPF Router ID. If there is no Loopback Interfaces configured, the highest IP address on its active interfaces is selected as the OSPF Router ID.
How does OSPF choose designated router?
OSPF DR BDR ELECTION
- Router with the highest OSPF priority will become a DR. Router with the second highest OSPF priority or router ID will become a BDR (By default, all routers have a priority of 1)
- In case of a tie, Router with the highest router ID wins the election.
What is router OSPF process ID?
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.
How do I manually configure an OSPF router ID?
If you want to change the router ID setting, do the following:
- Go to the global config context; the CLI prompt appears similar to the following:
- If OSPF is not enabled, go to Step 3; if OSPF is enabled, use no router ospf to disable OSPF operation.
- Use ip router-id ip-addr to specify a new router ID.
What will an OSPF router use if the router ID is not set?
If a router-id is not configured manually in the OSPF routing process the router will automatically configure a router-id determined from the highest IP address of a logical interface (loopback interface) or the highest IP address of an active interface.
What is the default priority for OSPF routers?
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. The following command configures a priority value on an interface.
How is router ID determined in DR BDR election process?
router with the highest OSPF priority will become a DR. By default, all routers have a priority of 1. 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.
Do OSPF process ID have to match?
Process ID numbers between neighbors do not need to match for the routers to establish an OSPF adjacency. The OSPF process number ID is an internally used identification parameter for an OSPF routing process and only has local significance.
How can I set process ID in OSPF?
To enable OSPF on a Cisco router and advertise interfaces, the following tasks are required:
- Use the command router ospf process ID to start OSPF.
- Use the network command to enable the interfaces.
- Identify area assignments.
- (Optional) Assign the router ID.
What is OSPF router priority?
Priority in OSPF is mainly used to influence/determine a designated router/backup designated router for a network. By default, the priority is 1 on all routers. A router with a high priority will always win the DR/BDR election process.
How does OSPF determine priority?
You can verify which neighbors are the DR/BDR/DROTHER by using the show ip ospf neighbor command in privileged mode. Configures an OSPF priority on a per interface basis used to manipulate the DR/BDR election process.