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Installing asa5505 between Comcast SMC switch and inside address

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tgoyette
New Contributor

Installing asa5505 between Comcast SMC switch and inside address

I am going to install an ASA5505 security appliance between my SMC appliance and my inside network.  I already have the 5 static IP addresses but would like guidance on what I need to change on my Comcast router and what information do I need to configure my ASA (see below)

 

  • I assume I use one of my static IP addresses for the outside interface of my firewall
  • Is there a specific domain name I should assign to the ASA
  • I plan on enabling the DHCP server on the ASA. Should I use auto configuration on my outside interface or manually input the DNS and WINS IP Addresses. If manual, what IP addresses should I use?

 

Trusted Forum Contributor

Re: Installing asa5505 between Comcast SMC switch and inside address

Hello tgoyette and welcome,

 

Please see my comments below.  Thanks.

 

 

 

  • I assume I use one of my static IP addresses for the outside interface of my firewall

    Yes. Typically on any Firewall or Appliance such device, you need to program the WAN interface with the static routeable, gateway, and subnet mask IP addresses. You may also need to internally program your ASA WAN interface as well which you can contact CISCO support for assistance. The Gateway address must be specified within the ASA Static Routing facility.  

  • Is there a specific domain name I should assign to the ASA

    There is typically no real intra or internetworking requirement for this.

  • I plan on enabling the DHCP server on the ASA. Should I use auto configuration on my outside interface or manually input the DNS and WINS IP Addresses. If manual, what IP addresses should I use?

    I recommend that you consider disabling the Comcast SMCD3G LAN DHCP server to avoid any DHCP conflicts with your ASA. Simply connect a computer via Enet cable (automatically obtain IP address) to any of the SMCD3G rear Lanports 1-4, bring up a browser, go to 10.1.10.1, username=cusadmin password=highspeed. Then click on LAN, put cursor on checkbox next to Enable DHCP Server and uncheck that box, press apply and you have just disabled that SMC DHCP server. It is alway good practice to add your Primary 75.75.75.75 and secondary 75.75.76.76 DNS addresses, too. Unless you are using really old computer OSs or have specific need to to support NetBIOS over TCP/IP (NetBT), WINS really are unneccessary these days.


    Hope this helps you out.