OSPF External Routes LSA Type 5

[abdul.qadir5001]

Why OSPF External Routes LSA 5 E1 is preffered over E2?

[balaji.bandi]

There are many documents already published  - with examples.

check this :

https://community.cisco.com/t5/networking-blogs/ospf-external-route-selection-algorithm/ba-p/3102714

OSPF Preferred Route Decision Order - According to section 11 of RFC 2328 , the order of preference for OSPF routes is:

– intra-area routes, O

– interarea routes, O IA

– external routes type 1, O E1

– external routes type 2, O E2

[Joseph W. Doherty]

Why E1 preferred over E2?  Well, RFCs often don't define why however my guess is since an E1 carries internal cost, it has "better" or "more" information, so its makes a more "informed" decision.