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dual wan (load balance two ISPs)

I'd like to do load balancing using a Cisco 2911

( instead of just failover as I am doing now with the ASA as based on...

http://www.cisco.com/en/US/products/hw/vpndevc/ps2030/products_configuration_example09186a00806e880b.shtml )

I've been looking at...

http://www.cisco.com/en/US/tech/tk648/tk361/technologies_configuration_example09186a0080950834.shtml

Where I'm not clear is how to ensure VoIP server traffic always goes out the T1, and never the DSL

and how to make two "static routes" (one from a T1 IP and one from a DSL IP to both go to the inside IP of the Mail server)

I realize I will have to update some static routes and rules in the ASA.

If you have any suggestions on the right way to do this, I appreciate your expertise.

See attached diagram

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Re: dual wan (load balance two ISPs)

Hello Rita,

>> Where I'm not clear is how to ensure VoIP server traffic always goes out the T1, and never the DSL

you want to go beyond destination based routing so you need policy based routing

see

http://www.cisco.com/en/US/tech/tk365/technologies_tech_note09186a008009481d.shtml

it has to be configured on the C2911 applied inbound on interface towards ASA per your network diagram

>> nd how to make two "static routes" (one from a T1 IP and one from a DSL IP to both go to the inside IP of the Mail server)

this means two NAT static entries, you can even define a port based TCP port specific ip nat static entry

see

The following example shows how to configure route map R1 to allow outside-to-inside translation for static NAT:

ip nat inside source static 10.1.1.1 10.2.2.2 route-map R1 reversible

http://www.cisco.com/en/US/docs/ios/ipaddr/command/reference/iad_nat.html#wp1041067

Edit:

after night thought: if you have deployed VOIP with distinct IP subnets used on both sites you can avoid PBR having specific routes advertised on the T1 link only,  on the DSL link you can place less specific static routes or less specific routes.

Most specific routes are used first and this can be used here.

Hope to help

Giuseppe

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