Hi, On ven. 20 déc. 22:36:29 2019, Nico Schottelius wrote: > > Hello, > > I was wondering about how bird solves the following problem with next > hop self enabled: > > R1 <--------> R2 > \ / > \ / > upstream 1 > > So both routers receive the same routes from upstream and insert them > with the same local_pref. With "next hop self" on, both routers will > think that the path is not the same and potentially either of the two > routers could start routing via the other router instead of via upstream > directly. > > What is the typical approach to solve this situation correctly? > Does making setting the local_pref lower if received from an > iBGP router make sense in that case? > > Best regards, > > Nico
There will be no loop because eBGP paths are preferred over iBGP ones if the routes are equals. https://tools.ietf.org/html/rfc1771#section-9.1 BTW, using classical iBGP, RRs and an IGP will solve many of this kind of problems. -- Alarig
