MPLS unequal cost Loadsharing

[MANOHARAN MUDALIAR]

Hello,

I have exiting Cisco 7600 in 4 location and bandwidth in 300 mbps. The sites are connected as ring so that we can achieve failover. now my organization is coming with additional 450 MBPS link on that same router. So please can anyone tell me how to achieve unequal cost loadbalancing between 2 link.

Note:

I am running MP-BGP for MPLS VpnV4 routes.

I am also running OSPF between the 4sites.

Please let me know if you require more information on topology..

Thanks

Regards

[Nagendra Kumar Nainar]

Hi,

Unequal cost load balancing is not possible with OSPF. You can try enabling MPLS TE to have 2 different TE via different path with static route enabled on head end to have traffic load balancing.

HTH,

Nagendra

[MANOHARAN MUDALIAR]

Hello Nagendra,

Do u mean that should I go with TE, as I understand I will use TE between the location where its required but then I have to use Static routing which will be again dependence, and it’s an SP Network so manually changing the route will be more hassle work for us.

[shreerampardhy]

Hello Manoharan,

As Nagendra pointed out, OSPF will always select a single route to any destination. TE can setup the tunnel to destination via dynamic path / auto tunnel options so that you can have minimal configurations.

BGP has an option of DMZ-link, which takes link bandwidth into consideration, but that is for the external links.

Another option that you might consider is to run two parallel ospf processes with neighbourship formed between the adjacent routes through different loopback address ( Eg:  PE1 ==== PE2 having two links of 300 Meg and 450 Meg. For the 300 Meg link, ensure that neighbourship is formed between the two routers usnig Loopback 0 and the second neighbourship is formed using Loopback 100 ).Change the BGP nexthop for some routes to point towards Loopback 100 and some routes to point towards loopback 0.  This will cause the traffic to be split across both the links without having TE.

Please note that the above option would require a lot of background work before it is deployed in live network.

Regards,
Shreeram