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cisco 1720 dual isp

I have a cisco 1720 router with one adsl interface, one fast ethernet and one ethernet. the user had just the adsl portion but now wants to bring in a second isp (cable modem) on the ethernet port. he also has a pix 515 with three ethernet interfaces behind the router.

first problem.

how do i load balance traffic between the two interfaces?

how will incoming traffic we redirected since he is running mail and web behind the pix?

can this be done?

any help will be appreciated...

Hall of Fame Super Gold

Re: cisco 1720 dual isp

Yes, it can be done. However to load balance the router needs to do NAT for all the interfaces. If you can meet this requisite, this is the config example:

Hope this helps, please rate post if it does!

New Member

Re: cisco 1720 dual isp

thanks for the reply. does this means firewall will have to be done at the router? the pix will have to part ways... there are also incoming traffic, will that be a problem.

thank you again in advance.

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