Network cDAQ Not Reachable Through Real-Time or Industrial Controller

Updated Jul 28, 2021

Reported In


  • Industrial Controller


  • Measurement & Automation Explorer (MAX)

Issue Details

I have a Real-Time or Industrial Controller (IC) connected to my local network, with a cDAQ connected to one of the secondary ethernet ports of the controller. However, when I try to add the cDAQ in Measurement & Automation Explorer (NI MAX), I receive the following error message:

This device is not reachable.

I cannot see any of the cDAQ modules, and I am unable to change network settings of the chassis.


This error is usually caused when the secondary ethernet port of the Real-Time or Industrial controller that you are connecting the cDAQ to is not configured correctly. The primary ethernet port of the controller (also referred as eth0 on NI documentation) is part of a separate Network Interface Controller (NIC) than the rest of the ethernet ports. Therefore, you need to make sure that the secondary ethernet port you are using is configured with a static IP that does not reside on the same subnet as the primary ethernet port. This is explained in more detail on Configure Dual Ethernet Ports on Real-Time Controllers. You also need to assign the cDAQ a static IP that resides on the same subnet as the secondary ethernet port of the controller.