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Exactly what ports are used to communicate with a cRIO?

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I have trouble with reseting my cRIO over the network behind a firewall. To solve this I used Wireshark to monitor a open network link and found it to use port 44516 for this. Can anyone verify this?





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Message 11 of 14

44516 is the device discovery port LabVIEW RT and MAX uses when the device is not on the same subnet. It uses 44525 when the device is on the same subnet.

National Instruments
RIO Embedded Hardware PSE

CompactRIO Developers Guide
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Message 12 of 14

Ok, but my computer and my cRIO are on the same subnet in my lab where I did the tcpip sniffing....And when I now opened this port in my remote system (same subnet through a cisco switch) I could finally reset the cRIO.

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Message 13 of 14

Since this thread keeps coming up in Google searches, I am posting an update of what I learned.

The two most applicable NI papers/documents pertaining to ports and remote access do not mention two crucial ports for remote restart operations (when remote target is behind a firewall with port forwarding).


Via Wireshark and NI Customer support, I managed to track my problem to two ports:


To reboot you need to forward/open ports 44515 and 44516. 44516 was mentioned above as the port used by MAX for discovery of devices on another subnet, which may or may not be related, but the reboot command is transmitted over DDP Protocol on ports 44515 and 44516.


I am now able to restart target from MAX, from LabVIEW project and from VI using system API or old deprecated 2011 version of RT Restart (IP).


NOTE: the DDP protocol (and associated ports) is not used in the new Zynq based targets!! (so this applies to older Pharlap and vxWorks targets.)


The two NI documents I mentioned are What Ports Do I Need to Open on My Firewall for National Instruments Software Products?  and  though neither mention these two ports.


I'm not sure why this information has to be so hard to come by.. hopefully this will help someone else save some time!?


CLD LabVIEW 7.1 to 2016
Message 14 of 14