What is the best advice for handling network and internet DNS routing?

Posted on 2007-08-08
Last Modified: 2010-04-20
I have a DNS Server that an outside company configured.  Today, all outgoing www traffic stopped dead.  Our computers are all configured to send DNS requests to that server at  I quickly figured that since we were still receiving email and our VPN was still up that it was a DNS problem and not that our T1 data line hadn't gone out.  So I looked in DNS and our www record appeared to have the address of our old email server instead of the internet DNS server that we use.  I replaced the address in the www record with a valid DNS server address.  

1. Is it correct to say that that mail server had been handling all of our internet DNS requests?
2. Can I add multiple www records for other DNS servers or is there no point?
3. Since we have DHCP running, would it be better to not use the www record and just set up DHCP to hand out the network DNS server address and also the internet DNS servers?
Question by:shoshe
    LVL 38

    Accepted Solution

    The www record in DNS has nothing to do with name resolution for Internet traffic.  The correct configuration is:

    1.  ALL internal servers and clients should be using your internal DNS server(s) as primary and secondary DNS servers.  If you only have one DNS server, you can leave the secondary blank.
    2.  DHCP is the easiest way overall to assign the DNS server address to your clients.  Again, in setting up DHCP, you want to use ONLY your internal DNS server address(es).
    3.  On your DNS servers, you can set up DNS forwarders to forward requests for external addresses to your ISP's DNS servers.  This is optional, however; all name resolution should work fine without it unless there is something wrong with your DNS server's configuration or their is an operational or network communication problem.

    Author Comment

    Thanks for the suggestion and it does help.  Is there a way to explain the complete network loss of being able to resolve internet addresses?   Everything else didn't stop, our VPN stayed up, Exchange email was still flowing, I could remote to a PC outside of the network.

    Author Comment

    OK, I think I got it.
    When I right clicked on our server in the DNS window and went to Properties, there is a tab that says Forwarders.  Those were configured with addresses other than those that I thought we were using.  Those servers must have stopped responding temporarily?  It was probably my ISP's problem, not ours you think?  I edited that forwarders record to include the addresses of the DNS servers I thought we were using.
    LVL 38

    Expert Comment

    by:Hypercat (Deb)
    Yes, I think you're right about the forwarders.  I've seen this happen before, which is why I don't necessary encourage people to use forwarders.  Everything should work just fine without them.  According to Microsoft, using forwarders can speed up name resolution for external addresses, and this might be true if your DNS server is carrying a heavy load.  However, I've not seen any noticeable advantage in the situations I deal with, which are mostly small networks (100 or fewer users).

    Write Comment

    Please enter a first name

    Please enter a last name

    We will never share this with anyone.

    Featured Post

    Highfive + Dolby Voice = No More Audio Complaints!

    Poor audio quality is one of the top reasons people don’t use video conferencing. Get the crispest, clearest audio powered by Dolby Voice in every meeting. Highfive and Dolby Voice deliver the best video conferencing and audio experience for every meeting and every room.

    There have been a lot of times when we have seen the need to enter a large number of DNS entries in a forward lookup zone. The standard procedure would be to launch the DNS Manager console, create the Zone and start adding new hosts using the New…
    Know what services you can and cannot, should and should not combine on your server.
    To add imagery to an HTML email signature, you have two options available to you. You can either add a logo/image by embedding it directly into the signature or hosting it externally and linking to it. The vast majority of email clients display l…
    Excel styles will make formatting consistent and let you apply and change formatting faster. In this tutorial, you'll learn how to use Excel's built-in styles, how to modify styles, and how to create your own. You'll also learn how to use your custo…

    779 members asked questions and received personalized solutions in the past 7 days.

    Join the community of 500,000 technology professionals and ask your questions.

    Join & Ask a Question

    Need Help in Real-Time?

    Connect with top rated Experts

    14 Experts available now in Live!

    Get 1:1 Help Now