BGP automatic load balancing

[olly ahmed]

Hi I am using dual homed connection and from both of my provider I am receiving default-route. I am using only one router to connect with both providers. Now my question is that can I load balance between these two connections. I mean is there any way to say my BGP router to use automatic load balancing between two. I the answer is yes then it will be convenient for me if you share a sample configuration.

[Philip D'Ath]

Yes you can do load balancing.

If you do a "show ip route 0.0.0.0" does it show two outbound options?  If so, it should already be load balancing.

If it doesn't, what is the output of "show ip bgp 0.0.0.0 0.0.0.0"

[olly ahmed]

I mean that is there any to load balance by bgp process which we can by ospf/eigrp by maximum-path commands. So my question is automatic load balancing possible by BGP ?

[Philip D'Ath]

I can't understand your grammar.  Would you like to try re-phrasing the question.

If you are asking about the number of paths used, you can control this using the maximum-paths command.

router bgp xx

  maximum-paths 2

You can also consult this guide:

http://www.cisco.com/c/en/us/support/docs/ip/border-gateway-protocol-bgp/13762-40.html

[Joseph W. Doherty]

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Posting

Yes you can, but as often the case with BGP, it's a bit more involved than your IGPs.

If I remember correctly (for Cisco), multiple BGP link peering (on same router) with the same remote AS will load balance across the links as long as you bump up maximum paths from its default of 1.  If your same router's multiple BGP link peering is with different remote ASs, you also need to use a secret/hidden command, bgp bestpath as-path multipath-relax.