3 Replies Latest reply on Jun 30, 2015 1:03 PM by noor

    Routing without NATing

    uvdstech New Member

      AT&T is hading me a fiber circuit that I have to but a router to "hand off" my public IP range to my firewall. (usually that peice of eqipment is provided by ATT, but not this time). I am trying to setup a 3305 to do just that, 1 interface with be ATT's /30 network address and 1 interface will have my Public IP range /28. I setup the appropriate IP's and default route in the 3305 but I cannot communicate past each interface. For troubleshotting, I installed a Cisco 2800 and just setup the Interface IP's and the route and it worked without issue. SInce it is a public IP handoff, I don't want NAT involved. What am I missing? Do I need to bridge something for the 2 interfaces to route between each other.    PS.. I was able to get the interfaces to talk, but only by NATing the Interface my Public IPs are assigned to, but the traffic would not route back.

        • Re: Routing without NATing
          cj! Beta_User

          Did you get this working? Definitely check the application guide linked by v-markb.


          If you merely need the 3305 to route all traffic between the /30 and your /28 network, without security policy, then you can setup the firewall so that both interfaces are in the same security zone (policy-class), say, Private.  Add a rule/policy to allow all traffic from Private to Private.


          If you need security so that the 3305 will act as a firewall, then I think your best bet is to setup the firewall so one interface is in a Private security zone and the other in Public, or similar.  Make a new policy/rule to allow all traffic from the Private to the Public zone.  Add policies from Public to Private as needed.


          Does this fit your project?  Let us know how it goes or if you'd like to see a configuration example.



            • Re: Routing without NATing

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