OSPF Router ID Election Order | Generated by AI
The correct answer is C) Manually configured > Highest loopback > Highest physical.
Here is the default OSPF Router ID (RID) election order in Cisco (and most standard OSPF implementations):
- Manually configured Router ID (using the
router-id x.x.x.xcommand under the OSPF process) → This takes highest precedence. - Highest IP address of any configured loopback interface (Loopback interfaces are preferred because they are always up).
- Highest IP address of any other up/up physical interface (if no loopback exists or none have IPs).
- If none of the above exist, OSPF won’t start (it requires a RID).
Summary of default order:
- Manually configured RID → wins always
- → Highest loopback IP
- → Highest physical interface IP (that is up/up)
So the correct answer is C.
(Options A and B are incorrect because they omit the manually configured RID, which has the highest priority. D is wrong — it’s never random.)