Re: AS_PATH length and route selection (WAS: Strange BGP announcement)

Ben Black wrote: | The key to this is that the administrative preference in question has domain | scope. Assuming you are correctly implementing iBGP, whether with a full | mesh, reflectors, or confederations, and assuming consistent announcements | from external route originators, then you can't make a loop because the | same policy is in effect for all the routers in the AS. You will not form a *persistent* loop or black-hole. However, as there is invariably some degree of propagation delay among iBGP speakers, particularly in a large network, there can be short-lived loops or black-holes when converging upon routing changes. Sean.