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ip conflict

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  • ip conflict

    got dhcp installed, but i often encounter a windows system error (there is an ip conflict with another system on the network).

    my dc and a member server are static but diff ips.
    how will i know the conflicting ips?


  • #2
    Re: ip conflict

    Which machine are you getting this error on???

    What is you DHCP scope?? Have you excluded all the static IP's that you have???


    • #3
      Re: ip conflict

      on the member server..

      the static ip is but the dhcp range is from -


      • #4
        Re: ip conflict

        Add an exclusion for the range that your servers are on and see if that works.

        Another option is to turn off your member server and ping the address that you have the conflict with using the -a option and see if it returns the computer name causing the conflict.


        • #5
          Re: ip conflict

          i did the second recommendation... ur right someone is using that ip... but i cant see the name of the pc. even if i used the -a option

          whats my next move/option


          • #6
            Re: ip conflict

            Have you chekced the DHCP console to see the address leases that the server is giving out???

            Does it show the .5 address at all???


            • #7
              Re: ip conflict

              Get the MAC address associated with that IP and trace it to which port in the switch that MAC is on. (Of course, this is contingent upon you having a managed switch that allows you to view that information.) When you find the port, trace the wire to the physical location and reconfigure the computer.
              Wesley David
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              • #8
                Re: ip conflict

                You could try setting the Collision Detection attempts to 2 on the DHCP server Properties under Advanced tab. If ever I need to recover DHCP, I set this option to better ensure only unique IP addresses are allocated. It basically pings the IP address for you before deciding whether to issue an IP. Then set the renewal interval to an appropriate level, so computers request a DHCP address sooner. It may not resolve your issue straight away but will be a good place to start to ensure other conflicts don't keep happening.
                Last edited by Virtual; 4th February 2009, 16:25.


                • #9
                  Re: ip conflict

                  Originally posted by Nonapeptide View Post
                  Get the MAC address associated with that IP and trace it
                  It may also be able to tell youwhat type of device it is which can sometimes help
                  Something like this
                  www. coffer. com/mac_find/

                  Please read this before you post:

                  Quis custodiet ipsos custodes?


                  • #10
                    Re: ip conflict

                    Or do a ping, then a arp -a.

                    No need for a third party product

                    Or do a portscan (nmap?) and check out if it's a windows machine.
                    Maybe it's a router, switch or a printer for example.
                    Technical Consultant

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