Posted on 2013-01-15
I have an industrial network which uses Hirschmann RS20 Ethernet switches in a redundant Fibre ring arrangement. The network unfortunately has evolved and there are unmanaged switches in various places.
The network has a lot of indutrial control gear such as Schneider PLCs, HMI, Rockwell & Siemens PLC's. There are also a few SCADA Systems that regularly poll the PLCs via OPC.
The system also has two safety PLCs that need to communicate with each other. The system has a watchdog time that when it times out will shut the safety system down.
The system regularly shuts down on timeout and also other system seem to have regular timeout issues.
I have been tasked with finding out
a) What is happening on the network.
b) Providing a solution to cure these timeouts.
c) gaining a better understanding of network troubleshooting.
It is a big subject, but I thought the first point of attacks is to see what is happening between the two systems. I have a copy of wireshark but need some guidance in using the product in conjunction with the network switches to enable me to monitor all the traffic.
With the switches on the switches on the network, I can used port mirroring to monitor a specific port using my laptop PC.
Is their any other way or a better way to monitor the network. I am acutely aware that I will need to trawl through an awful lot of data!
The question is fairly vague as I am new to this type of work, although I am reasonably computer literate.