Loadsharing outbound upstream traffic in bgp

[truideman]

A question;

How can i loadshare outbound upstream traffic in a bgp multihomed sitiuation whereas iam peering with 2 diffrent AS's.

Iam only receiving a default-route from my upstream peers.

[MHM Cisco World]

this lab for you and this what you looking for

[truideman]

Thanks for your lab.

Iam running IOS-XR and iam wondering what the command would look like since i only see the command "multipath" in the bgp configuration.

[MHM Cisco World]

max-path I think for IOS-XR found under the address family 

[paul driver]

Hello

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@truideman wrote:

How can i loadshare outbound upstream traffic in a bgp multihomed sitiuation whereas iam peering with 2 diffrent AS's.
Iam only receiving a default-route from my upstream peers.

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You dont mention if this is a single/dual wan rtr , if its just a single rtr with two ebgp peers then you could apply two default static routes which should overide your received defaults and provide you with egress L/B

[truideman]

Hi Paul,

The problem with adding default-routes toward upstream is that in case something happens in the upstream transmissionpath traffic would be ending up blackholed since the upstream port of the internal bgp router isn't aware of any transmission problem. 

[truideman]

In mean traffic could be blackholed because the upstream interface stayed UP.

[paul driver · Accepted solution]

Hello
Your two default static routes will be condictional so that you would track the upstream connectivity as such if the sla failed it would remove the related default.

[truideman]

Thanks Paul

I will try this solution out.