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New Member

The OSPF load balance Problem.

Dear all,

I have one question about the OSPF load balancing.

Our Lan segement is using the Router A Ethernet interface as the gateway. And the serial links S0 and S1 of the router A are connecting to the ISP routers Router W1 and Router W2 respectively. The Router W1 has one T1 to the ISP 1 and the Router W2 has two T1s to the ISP2. The router A, Router W1 and Router W2 are all running the OSPF. My question is whether there is any good suggestion about doing the load balance in 2:1 ratio for the Router W2 to the Router W1. Thx a lot for your help.


Tony Kwok

New Member

Re: The OSPF load balance Problem.

To the best of my knowledge, OSPF only supports "equal cost" load balancing. The above would not be equal, so it would pick only one path, or at best, do load balancing across them evenly. EIGRP supports unequal load balancing.


Re: The OSPF load balance Problem.

OSPF only supports equal cost paths. While EIGRP supports unequal cost load sharing, it's usually more trouble than it's worth and not highly recommended.

You might consider investigating trading routes with your ISP via BGP. Depending on you and your ISP's setup, it's possible you will be able to acheive some level of load sharing by advertising/learning routes with the ISP.

New Member

Re: The OSPF load balance Problem.

OSPF supports equal cost load balance,but you can try configing your Router A's S0 and S1 the same bandwidth to spoof the Router processer.

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