I know the difference between E1 and E2 metric-types. I know the preference level given to those routes. I know difference between Metric and Forwarding Metric and how it works.
What I don't understand - why this two type of E1/E2 exist ? Is there any special reason for those two types of metric to exist ? If forwarding metric is used for to find the best path to get the ASBR. then the E1 routes carries the same kind of information ( route cost at distribution point + best path cost for the ASBR).
Can someone give me a real world example where should we use Type-E1 over E2 ? or wise versa.
If I redistribute into OSPF via multiple ASBR, default E2 Cost 20 will remain through entire OSPF domain. Then the local router will use the Forwarding distance + Metric(20) to reach the external LSA 5. Ultimately I would achieve the same result if I redistribute the same route via multiple ASBR as a Type E1.
Am I missing something ?
Sajith Happy Routing!