Hi Abdel, > During my study I have understood that when the router peer with its > neighbor it compare its own AS # with the neighbor AS# to decide whether its > IBGP or E-BGP neighbor.
This is the case. R1 and R2 still see each other as eBGP neighbor. But as you pointed out, when you use the local-as command, the router prepends its real AS # by default. And as R1 and R2's real AS # are the same, the BGP loop prevention enter in action: Routers refuse all NLRI containing their own AS # in the AS_PATH. (You can see it with "debup ip bgp updates"). Your workaround simply prevent the routers to prepend their real AS# and to replace it by the fake AS# (or local-as). Another option could be to use "neighbor x.x.x.x allowas-in" command. This disable the AS_PATH check for updates coming from that neighbor. Regards, Christophe _______________________________________________ For more information regarding industry leading CCIE Lab training, please visit www.ipexpert.com Are you a CCNP or CCIE and looking for a job? Check out www.PlatinumPlacement.com
