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There is an interesting usage of the Cisco ACE to balance output internet traffic through different ISPs, as explained here.

Basically, it would be set on ACE the ISPs border routers as the rservers, a server farm in transparent mode (no NAT in the destination addresses), SNAT pool in each ISP VLAN and a VIP that would be used as the default gateway on your network.

Has anyone implemented this? In other words, has anyone used an ACE to load balance a pair of routers?

Note: A router running BGP would be a better solution, but it is not always an option.

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Seems overkill for a very simple issue, why not just create two static routes on the border router. One for half of the internet addresses out of one ISP, and another for the other half of internet addresses out of the other ISP. – iTom Jun 5 '12 at 17:06
iTom, good point! The problem is that the majority of the access are local. But... your idea is valid (and simpler), I just have to split the most used ranges and, as a backup, two default routes with different metrics tied to an ip sla track point to each one of the ISPs, as I am using a Cisco ASA on my end. – Adriano P Jun 11 '12 at 18:52

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