2 Replies Latest reply: Mar 7, 2012 11:18 AM by mtuma RSS

    Access Rule based on a on a DNS Domain


      Hi List,



      i want to create a access Rule for a network for access the Windows Update Services.


      But neither i know the Ip Adresses nor the complete fdqn of the Hosts.


      The Rule should include something like this:






      and so on. But can't use Wild Cards in this way on a Access Rule.


      can someone please tell me, how to accomplish this?


      We are using Sidewinder 8.




      thanks in advance



        • 1. Re: Access Rule based on a on a DNS Domain

          You can create "Domain" network objects like this:-



          and this essentially means "*.windowsupdate.com". If you create domain objects for windowsupdate.com, update.windows.com, windowsupdate.microsoft.com and then put these objects into a netgroup (though I think in v8 you can specifiy multiple endpoint values) you should then be able to create a rule to control outbound access to these locations.


          The Firewall doesn't have the capacity to control access by specific URLs (though you could try using SmartFilter to do this), but an outbound rule for the HTTP application to these destinations should do the job.


          Hope that helps.


          • 2. Re: Access Rule based on a on a DNS Domain

            Phil is absolutely correct. It is important however, to understand how domain objects work. They rely on reverse DNS to work, and unfortunately reverse DNS is not always reliable. Basically what will happen is you make a connection to x.x.x.x. The firewall takes x.x.x.x and does a reverse lookup on it to find the PTR record. If the PTR record domain matches your domain object, then the traffic will be allowed (or denied).


            Smartfilter is the best bet in this case. Smartfilter does not have to rely on reverse DNS, it simply looks at the URL of the request.