[c-nsp] propagate learned MED to peers?

[Rainer Clasen]

Hello,

ususally cisco does not propagate the MED learned from other peers to a
different AS. Well, usually this is fine.

Consider an AS with several Confeds. Each Confed originates it's own set
of routes. Each Confed has it's own IGP. All Confeds peer with the same
upstream provider. To save capacity in your own backbone, you want the
upstream provider to send the traffic preferrably directly to the
Confed, where the prefix originates.

In a non-Confed scenario I'd use metric-type internal for setting the
MED. As you have no continuos IGP throughout the Confeds, you can't use
this. 

My idea was to increase the MED on each confed boundary and announce
this calculated MED to the upstream provider. Of course you have to be
quite careful with MEDs you receive from peers. Unfortunatly Cisco nukes
the MED, before it is announced.

Well, I can set the MED manually based on communities, as-path or
friends, but this is a hassle to maintain.

Is there a way to announce the learned MED to external peers? Is there
another way to accomplish this?



Rainer

-- 
KeyID=759975BD fingerprint=887A 4BE3 6AB7 EE3C 4AE0  B0E1 0556 E25A 7599 75BD