TCP Communication Problem between Windows 11 host and cRIO 9057

[Universaldilletant]

Dear Community,

the following image explains my problem:

- Windows 11 Computer with LV23Q3

- cRIO 9057 with LV Realtime 23Q3

- Same subnet, different IP addresses, connected via network switch. Nothing else on the network: Laptop - Switch - cRIO

- They can ping each other (Windows to cRIO on powershell works, cRIO to windows via Linux shell works)

- The control via NI Max of the cRIO works fine

- Running any VI on the cRIO works

- Running the "Simple Network Streams.lvproj" works just fine

But:

- The "Simple TCP.lvproj" does NOT work, for whatever I do

    - I tried a number of ports

    - I disabled all firewall functionality on windows side

    - I tried the project with TCP Server and Client on the same machine which works

    - But no parameter establishes the connection between TCP Server and Client if I run them on windows and cRIO

I have gone through a couple KBs:

- https://knowledge.ni.com/KnowledgeArticleDetails?id=kA00Z0000015A3ESAU&l=en-CH

- https://www.ni.com/en/support/security/configuring-software-and-hardware-firewalls-to-support-nation...

- https://knowledge.ni.com/KnowledgeArticleDetails?id=kA03q000000x4LuCAI&l=en-CH

But there is nothing, that I found that helps me.

Do you guys have any idea?

Thanks in advance for any help provided!!!

Cheers,

Niko

[joerg.hampel]

Hey Niko, are you familiar with Wireshark, a network protocol monitor and analyzer? It's a very handy tool in cases like this. It's fairly simple to operate, maybe give it a try and see what you can learn from monitoring the network.

Btw, any error codes you can share? What exactly does "not work" mean?

[Universaldilletant]

Hi Jörg,

wireshark ist a great idea 🙂
You are correct, my description was not really complete there: the initiation of the TCP connection errors out with a timeout error. On the server side:

on the client side:

Thanks for your help!

Cheers,

Niko

[Universaldilletant]

Hi Jörg,

I just switched the TCP Server to the cRIO and the client to the PC and it worked immediately.

I have no clue why this works now, but anyway , I guess I won’t find that out…

Cheers, Niko