can someone please tell me the difference between summary address vs area range in OSPF.
The former summarizes external networks, the latter is for inter-area summarization.
One is used on an ABR, the other is used on a ASBR. When using the area range command, the ABR will generate a type 3 LSA. The summary-address is used on an ASBR to summarize external routes being redistributed into OSPF.
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