5 Replies Latest reply on Jan 9, 2008 10:54 AM by boohbah

    Cannot install ePo agent on NLB servers

      Dear Experts,

      I have ePo 3.6.0 installed, and when I remotely "Send Agent Install" package on one NLB server (lets say it is ServerA), it gets installed successfully, however when I install it on another NLB server (ServerB), it gets intalled and connect with the ePo server, however the entry ServerA disappears and gets renamed to ServerB automatically.

      I've been told that this happens because NLB servers share same IP, however it was working fine in my previous ePo 3.5 installation, is there a way to fix this issue ?
        • 1. RE: Cannot install ePo agent on NLB servers
          Are you sure the servers have unique GUIDs within the registry?

          Sounds like the server is performing a wakeup after the install has finished and therefore replacing the existing server in the ePO database.

          There are many articles regarding duplicate GUID fixes.
          • 2. RE: Cannot install ePo agent on NLB servers


            Hi PBateman,
            I developed a script to get me the list of the GUID numbers of the NLB server, I get different numbers on each server.

            Is there another reason why this is happening ???
            • 3. RE: Cannot install ePo agent on NLB servers
              the problem is that ePO is initially differentiating the machines by their MAC address, and since they are NLB, the MACs are the same,

              you need to create a key called DIsableMACSearch - there are instructions in the KB,, and readme's,

              HTH,
              • 4. RE: Cannot install ePo agent on NLB servers
                Thank you so much boohbah,

                creating DIsableMACSearch key solved my problem.
                • 5. RE: Cannot install ePo agent on NLB servers
                  excellent - pleased to help.

                  DisableMACSearch is a double edged sword tho,

                  consider the following scenario :

                  i have a managed computer, it goes wrong, and i rebuild it from scratch, redeploying the agent

                  - the agent will generate itself a new AgentGUID , and contact the ePO Server.

                  if DisableMACSearch is not set, then ePO will use the MAC address as the initial differentiator, ePO will recognise the MAC address, and so update the directory entry with the new properties - no duplicates will be created in the directory.

                  if DisableMACSearch is set, when the newly rebuilt computer connects home, with a new Agent GUID epo will ignore the MAC Address, and say " i dont recognise your AgentGUID, so you must be a new computer, that happens to have the same hostname as another one of my managed computers" a new directory entry will be created, which will result in a duplicate machine.

                  the other scenario is that where 2 genuinely different machines share the same MAC address , ie NLD servers, teamed NICs, clustered computers, computers assigned a MAC address by a VPN client etc etc.

                  in order to tell them apart, DisableMACSearch must be set, but at the risk that you are overriding one of ePO's inbuilt algorithms for preventing machine duplication,

                  hth,