3rd post in the quick series is about BGP local-as

BGP Local-AS

“The local-AS feature allows a router to appear to be a member of a second Autonomous systems (AS), in addition to its real AS. This feature can only be used for true eBGP peers. You cannot use this feature  for two peers that are members of different confederation sub-ASs”


Requirement – R1 needs to peer with R2 with As number 400 while all other Routers to peer with R2 should use a AS number of 200



As we can see, R2 is acting as Local-as 400 for R1 and AS 2 for R3