• Creator
  • #2150459

    DSL DNS WIERD beat the best at qwest and Motorola


    by jbelknap ·

    I have a new DSL connection. It’s Qwest based, uses a Motorola DSL modem.

    Here’s the wierd part: modem connects to dsl line fine. Full configured, provides dhcp fine to client computers, from within the modem it does Name resolution fine.

    Client XP windows machine set to use DHCP, and automatically obtain dns.

    Client sucessfully gets a dhcp address of and assigns the dns as (the modem’s lan port).

    Should work RIGHT? Nope. I can ping any address by ip, but not by DNS.

    Hardcoded a dns server in the Nic card, same result.

    Now the really weird part. my test computer has been on my company network. Even though it correctly picks up the dhcp and dns addresses (without allowing dns to resolve), when I do a nslookup, nslookup defaults to the company private netted dns, it completely ignores what I have put on the nic. I’m thinking this result is part of my failure to resolve.

    It does this on 3 different company computers I’ve tried on this DSL connection. Could it be that some sort of policy has set these machines to ignore the dns setting of the nic cards and only to look for the company dns?

    I can’t believe 3 different computers have a stack error.

    Qwest, motorola, techs, and admins stumped on this one.

    any ideas what to try next? (and yes OF COURSE, we’ve ipconfig /flushdns, static IP’d the box, rebuild the DSL circuit, and replaced the modem)

All Answers

  • Author
    • #2924404


      by jbelknap ·

      In reply to DSL DNS WIERD beat the best at qwest and Motorola


    • #2924392


      by robo_dev ·

      In reply to DSL DNS WIERD beat the best at qwest and Motorola

      can your client ping the ISPs DNS servers?

      So is your topology single DSL modem directly to PC?

      If you hard code the ISPs primary/secondary DNS servers in the client, does everything work fine?

      Is there anything in the PC host or Lmhosts file?

      It IS entirely possible that a hosts file setting, lmhosts setting, or some policy setting such as subnet prioritization could be messing this up.

      ipconfig /displaydns

      That command should show the status of the DNS resolver cache and should shed some light on the issue

      And last but not least, personal firewalls must be configured to allow DNS queries to occur.

      • #2924389


        by jbelknap ·

        In reply to Clarify

        Yes, the client can ping the isps dns servers

        Yes the current topoogy is single dsl modem connected directly to the pc

        No, the problem still exists even if I hard code the isp’s primary secondary dns servers in the client

        Nothing in the PC host or LMhosts file

        Will check the files in the morning to be sure

        there are NO firewalls turned on (turned off by system policy) you say I HAVE to turn the windows firewall on in this topology?

    • #2924369

      Where does your

      by rob miners ·

      In reply to DSL DNS WIERD beat the best at qwest and Motorola

      Gateway fit into this connection.

      • #2922983

        Where does your gateway

        by jbelknap ·

        In reply to Where does your

        The gateway is the modem, so it’s ip is

        • #2922912

          Have you tried?

          by mpace ·

          In reply to Where does your gateway

          ipconfig /flushdns

        • #2922694


          by rob miners ·

          In reply to Where does your gateway

          When I setup I normally use:
          Primary and Secondary Address of ISP for DNS.
          DHCP will allocate an IP Address.
          The Modems IP as the Gateway.

    • #2923414

      FOUND IT!

      by jbelknap ·

      In reply to DSL DNS WIERD beat the best at qwest and Motorola

      We found the problem. It appears someone at some time enacted a group policy that set the dns. This caused the laptops and other company computers to retain the dns settings despite what the Nic card had set.

Viewing 3 reply threads