Announcement

Collapse
No announcement yet.

Strange behaviour resolving hostname

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • Strange behaviour resolving hostname

    I have a strange problem on my XP workstation at home. It seems that sometimes when I open a cmd window and try to reach a host I can't resolve the name.

    If I ping a hostname then I get
    Code:
    ping hostname
    Ping request could not find host hostname. Please check the name and try again.
    but when I immediately do
    Code:
    nslookup hostname
    Server:  dns1.mydomain.com
    Address:  10.0.0.8
    
    Name:    realname.mydomain.com
    Address:  10.0.0.8
    Aliases:  hostname.mydomain.com
    it shows dns working fine. If I then repeat the ping command expecting it to find the host it again fails the same.

    I am a dns administrator and am very confident regarding how this is supposed to work. I don't see why it fails to resolve the host when it worked fine a few mins ago. I am convinced this is a problem with the workstation.

    I have checked the hosts file to make sure there is nothing short circuiting the name resolution method and can see that the file is empty.

    The dns server is not loaded, it is connected to the same 100Mbit switch as the workstation and there is no other heavy traffic going on at the time.

    I just flushed the cache and it works again now. But I don't understand how this could happen. This setup is very simple compared to what I usually do. At exactly the same time I try these things from my Linux laptop it works fine showing that the problem appears to be confined to this workstation.

    The next time this happens I will look at the actual dns cache itself (can't now since I just flushed it - Doh).

    Any ideas or feedback welcome.

  • #2
    Re: Strange behaviour resolving hostname

    Do you have WINS installed on your network at all??

    Have you have a look in your LMHOSTS file??

    Comment


    • #3
      Re: Strange behaviour resolving hostname

      Is the host you're trying to reach have a dynamically assigned IP? If so could it be that the host updated its record?
      (stab in the dark)
      If it happens again, a look at the cache would be interesting.
      Keep us updated.
      Thanks for the post.
      Regards,
      Jeremy

      Network Consultant/Engineer
      Baltimore - Washington area and beyond
      www.gma-cpa.com

      Comment


      • #4
        Re: Strange behaviour resolving hostname

        there is no wins or lmhosts, the ips are static.

        I think this is a software glitch caused by 3rd party stuff on the machine or temporary corruption of the dns cache.

        I've got another problem with this same workstation's dvd-rw stopping working unless I remove driver and reboot and reinstall driver, it works for a while then breaks again and I have to repeat, but that is another thread.... http://forums.petri.com/showthread.php?t=11502

        So something funny is going on with this workstation...

        Comment


        • #5
          Re: Strange behaviour resolving hostname

          You stated
          The dns server is not loaded
          Are you sure the target is answering pings? If running the MS Firewall, make sure the target machine Allows incoming echo requests under ICMP settings in the Advanced tab.

          Being XP, is the DNS Client service running?

          On clearing the cache suggestion, have your tried an NBTSTAT -R?

          I take it TRACERT does the same as PING?

          Grasping at straws here.

          One of those problems that if I could tunnel in, I'm sure I could resolve in less than an hour (not an offer
          Cheers,

          Rick

          ** Remember to give credit where credit is due and leave reputation points sigpic where appropriate **

          2006-2099 R Valstar. This post is offered "as is" for discussion purposes only with no express or implied warranty of any kind including, but not limited to, correctness or fitness for use. Nothing herein shall be construed as advice. Attempting any activity based on information in this post is done at your own risk.

          Comment


          • #6
            Re: Strange behaviour resolving hostname

            actually I made the mistake of fixing it in 5 mins without finding the root cause.

            I will do this the next time it happens.

            dns client must be running since it works a moment later and I didn't restart it.
            tracert gives the same.

            Comment


            • #7
              Re: Strange behaviour resolving hostname

              The route is not the problem. You'll notice that ping didn't resolve the hostname. It therefore didn't have an IP address to try and route to. If the route was the problem then you would see an IP address and either Request timed out or Destination host unreachable...
              I guess I'm not really telling you guys anything you don't already know.
              Regards,
              Jeremy

              Network Consultant/Engineer
              Baltimore - Washington area and beyond
              www.gma-cpa.com

              Comment


              • #8
                Re: Strange behaviour resolving hostname

                Sometimes we know stuff but it doesn't always come out.

                Of course tracert will have the same problem as ping -- how silly of me.

                Now looking at the nslookup output, has the original poster tried pinging the fully qualified name?

                ping realname.mydomain.com

                or

                ping hostname.mydomain.com

                If so, is there something misconfigured in the workstation's TCP/IP network config under the Advanced/DNS tab regarding the DNS Suffix?
                Cheers,

                Rick

                ** Remember to give credit where credit is due and leave reputation points sigpic where appropriate **

                2006-2099 R Valstar. This post is offered "as is" for discussion purposes only with no express or implied warranty of any kind including, but not limited to, correctness or fitness for use. Nothing herein shall be construed as advice. Attempting any activity based on information in this post is done at your own risk.

                Comment


                • #9
                  Re: Strange behaviour resolving hostname

                  Originally posted by rvalstar View Post
                  If so, is there something misconfigured in the workstation's TCP/IP network config under the Advanced/DNS tab regarding the DNS Suffix?
                  I was thinking that too at first but when the DNS cache was cleared the problem went away...
                  Regards,
                  Jeremy

                  Network Consultant/Engineer
                  Baltimore - Washington area and beyond
                  www.gma-cpa.com

                  Comment


                  • #10
                    Re: Strange behaviour resolving hostname

                    Oh well, guess we'll have to wait till it happens again. I believe the appropriate idiomatic expression is "A watched pot never boils".
                    Cheers,

                    Rick

                    ** Remember to give credit where credit is due and leave reputation points sigpic where appropriate **

                    2006-2099 R Valstar. This post is offered "as is" for discussion purposes only with no express or implied warranty of any kind including, but not limited to, correctness or fitness for use. Nothing herein shall be construed as advice. Attempting any activity based on information in this post is done at your own risk.

                    Comment

                    Working...
                    X