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New Member

Load Balancing into OSPF

I have 2 E1 Lines with different services providers. How can i load balance between to links using ospf? Is there any configuration needed?

4 REPLIES
Silver

Re: Load Balancing into OSPF

Hello,

Yes it is possible, however the cost must have the same, because OSPF does not support unequal cost load balancing (as opposed to EIGRP where you can set up the variance)

Kriszti?n

New Member

Re: Load Balancing into OSPF

Thanks for reply..my que. is Is there any extra configuration needed?

jayesh

Silver

Re: Load Balancing into OSPF

If both link have the same ospf cost you don't have to tune it.

If not the same you have to configure the interfaces to get same cost on both links.

Krisztian

Hall of Fame Super Silver

Re: Load Balancing into OSPF

jayesh

There is not any extra configuration required in OSPF to load balance over two links if the same prefix (same destination) is advertised over both links and if the OSPF metric is the same for both prefixes over both links. This is the default behavior of OSPF - it will by default load share when it has two equal cost paths to the same destination.

However I question whether you will be able to load share over 2 E1s when the E1s go to different providers. Will both providers be advertising the same prefixes (same destinations)? And will they advertise the prefixes with the same metric?

It seems to me that it would be easier to not worry about OSPF with the providers and to just run OSPF within your own network and to configure 2 default static routes, 1 to each provider, and to let the 2 static routes load balance, which they will do by default.

HTH

Rick

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