ASA connected to two ISPs

Unanswered Question


I have an ASA 5520 with 4 interfaces. At the moment is connected to an ISP-A via its outside interface; and to an inside private network A via inside interface.

I would like to connect another ISP-B and create a DMZ. I want to route to the new ISP-B some other private networks B.

I will also have some static translations using IPs from ISP-A

Can you please point me in the right direction. Specially i am wondering if i can have two default routes, and if each translated pool will use the right interface.

Thanks in advance


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dhananjoy chowdhury Fri, 10/02/2009 - 11:19
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On the ASA, you can add upto 3 equal cost default route entries per device,but when defining more than one default route, you must specify the same interface for each entry.

But if you want to have two ISP's on two different interfaces, then you will have to opt for primary/Backup scenario, such that when the primary link fails you can use the backup link.

Here is an example.

However, it may not be possible to achive load balancing using both Internet links.


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