I am working on a project, which has the following type of hardware setup.

A special hardware device is receiving data from an external network interface. So we can have multiple such a hardware devices. Now these hardware devices will route the captured incoming data through the external network to a software running on a single PC through LAN.

If we run a single setup of the software in the LAN on a single PC, our software works with no issue.

The problem comes when we deploy two Ethernet card within the PC where the software is running. With the aid of two Ethernet interface we simulate two setup of the same software on the same PC within two different environments. Each software maintains a different setup of the network card it has to interface with.

The final setup in this case looks something like this. The two-network cards are separately connected to two different HUB port from the PC where two setup of software are running. The hardware devices, which capture incomming data from the external network, are also connected to the same HUB to different ports. Each of these hardware devices have been configured to talk to respective network cards within the LAN.

The problem is that each software environment states that some data packet is reported to be lost and if we bring down one of the software environment the error stops occurring.

Can anyone guide me that how can I trace the incoming data via the network from the LAN? Is it really a network problem? Why is that the problem stops occurring when we only run one such a setup of the software? What should be my approach to solve such an issue?

We are running the software on an AIX Ver 5 box.

Thanks in advance.