I have a fresh new setup, updated network configuration to do "Passive and Active." discovery, all servers and devices are discovered except a D-Link switch.
First of all, I have a 2 or 3 machines who have 2 or 3 NIcs, in the "entire network" list, those machines are repeated in the list as the same number of Nics.
2nd, under all discovered machines, there is Nic icon flagged with "Unknown" as you can notice in the attached snapshot.
When I try for example doing a map layer2, my router as seed, I get only 2 nodes, one for the router, second for the subnet nothing else. I expect to see a map of all servers connected to router!!!
If you install netxms agent on these machines (and add the address of your netxms server to MasterServer or ControlServers or Servers in agent configuration) then netxms would be able to get information about network interfaces. The other option is if SNMP daemon is running on the machines.
Without that netxms can only see that there is a machine and can ping it to check if it's running. But it can not determine that two addresses belong to same machine.