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bgp outbound traffic load balancing

I have 3 internet providers . I have 5 access routers running iBGP between them.  I use pre-pends to do inbound traffic load balancing . I have a problem doing outbound load balancing . Some  body out there help me with this
3 Solutions
I am assuming you want to load balance your Internet traffic via 3 ISPs.

In this case, load balancing is impossible but you can do load sharing.
Load balancing is not possible in a multihomed environment with multiple ISPs. BGP selects only the single best path to a destination among the BGP paths that are learned from different ASs, which makes load balancing impossible. However, load sharing is possible in such multihomed BGP networks. On the basis of predetermined policies, traffic flow is controlled with different BGP attributes.

You can use Local Preference attribute to load share outbound traffic.  
To provide exact configuration, please share more details.

nayan panchal


You can actually do  load balancing with BGP.

You can find the information over here:

set maximum-paths eibgp 3 under the address-family ipv4 vrf xxxx in your BGP configuration, than it will use the ebgp and the two ibgp paths to the external network.
care must be taken, if you set this on more than one router than it can easily happen that the traffic will be sent back over the ibgp path.
it is a design concept where to configure it, cos if the router dies than no load-sharing will be available.


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