[j-nsp] include-mp-next-hop

[Pedro Roque Marques]

Daniel Roesen writes:


> I wonder wether enabling/disabling include-mp-next-hop affects only
> direct peers or wether it is transitive throughout IBGP.

It is a non-transitive issue. It is mostly a matter of encoding
between two peers.

> To be more
> specific: will disabling the option on one router affect also
> routers on the other end of the network, across at least one level
> of route reflection?

No, the information enchanged in both circusntances is the same. The
only difference is that w/ include-mp-next-hop you send 4 bytes of 0s
w/ a null NEXT_HOP attribute that will be ignored.

> I fear that some BGP implementations might
> "cache" somehow wether a NEXT_HOP attribute was received or not and
> will re-announce accordingly.

No, the 0.0.0.0 NEXT_HOP is simply ignored.

In summary, dont use the include-mp-next-hop knob. Unless you happen
to be interoperating w/ a box that absolutly requires it. Probably
time to deprecate it and hide it in the config since i don't think
this is actually required any longer.

  Pedro.