Cisco Router : Determine incoming ports on interface?

Posted on 2011-10-25
Last Modified: 2012-05-12

An application we use on the outside is trying to get through our router, but uses other ports besides 443. I am only forwarding port 443. How can I see what ports data is trying to arrive on going to a specific internal IP? Then I can forward those ports too.
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    Accepted Solution

    If you have an acl on your outside interface, you can add the log command to the ip deny any any line and then look at your logging to see what is being denied.

    deny ip any any log

    at the end of the inbound acl.

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