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determine mac address of adapter without IP

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  • determine mac address of adapter without IP

    Does anyone know of a way to determine the mac addresses of adapters within a collision domain but without ip addresses - for example the mac address of a bridge or ports on a vlan or an adapter configured only for IPX or Appletalk

    MAC scanner and Lanspy only seem to be able to find the addresses of adapters with assigned IP addresses. doing an arp-a will also not work in this case


  • #2
    Re: determine mac address of adapter without IP

    Following a for "traceroute mac address" I hit this:

    Ping Scanner Pro has 18 network tools, it can ping one address a lot of times or a lot of addresses one time. It will also tell you what MAC addresses are on your subnet, and perform DNS lookup or reverse DNS lookup. It does Traceroute, Whois.
    Not tested, so no idea how effective in your scenario, but worth a try
    Tom Jones
    MCT, MCSE (2000:Security & 2003), MCSA:Security & Messaging, MCDBA, MCDST, MCITP(EA, EMA, SA, EDA, ES, CS), MCTS, MCP, Sec+
    IT Trainer / Consultant
    Ossian Ltd

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


    • #3
      Re: determine mac address of adapter without IP

      ok, on my Win7 machine I have a number of adaptors.

      THe bluetooth, for instance, does not have an assigned address of any type.
      doing ipconfig /all will show me the MAC for that adaptor. It also provides it for other adaptors, even if they are disconnected.

      From a switch, you can usually do sh arp or sh mac-address-list or similar within IOS, and that'll give you lists of MACs that cxan be seen on individual ports of the switch - both the client, and the port itself
      Please do show your appreciation to those who assist you by leaving Rep Point


      • #4
        Re: determine mac address of adapter without IP

        Thank you for the suggestions. I have been consulted about some network problems at a remote site and what i had hoped to do was to determine the network topology including any low cost switches or bridges that were part of the network - without having to physically go out to the site. I have had problems on occasion with two autosense ports connected together and there is also the possibility of bridging loops.

        I know that through the IOS i can determine the mac addresses of the ports of the router. pings and arps can determine the mac addresses of the target machines with ip addresses but there does not seem to be any way of determining whether the connection is direct, through one switch or two. Spanning tree would help but it is often not implemented on consumer grade switches.

        so what i would need is a layer 2 broadcast ping - this is in theory possible on some gear with a raw ethernet frame and an ethertype 0x9000 but seems to have dropped out of the current standard and there don't seem to be any programs implementing this feature anyway

        I guess i will just have to get in my car, go out there and trace the wiring manually



        • #5
          Re: determine mac address of adapter without IP

          Spanning tree is most always built into any switch.(check for 802.1D compliance)It may just let you run a single instance of it but nonetheless its still a spanning tree instance. Most unmanaged switches have this. Even 20 dollar linksys switches use spanning tree.

          show cdp neighbors will take of neighboring cisco devices. Wont help with other devices though. With all cisco gear you can map you layer2 network using some sh cdp commands and looking at the spannning-tree configuration.

          With ethernet we do have a all nodes broadcast address


          or for a particular network:

          If the swithches are unmanaged then their not going to have managed ip's. You can look at the port state in the spanning tree output on the cisco switches. If there are redundant links spanning-tree will block on one those ports to prevent the loop. Know if you dealing with hubs this could be an issue as they have no spanning tree function.

          To be honest its always better to go out and physically inspect the cabling. Then you will know exactly how its configured and then you can document it for future use
          CCNA, CCNA-Security, CCNP
          CCIE Security (In Progress)