Unable to access Networked Shared Variables from certain computers in the network

[Sabier]

This is my first time posting on these forums, so please forgive me if this is not the place or the way to ask for help regarding my problem.

I am trying to set up Networked Shared Variables between three computers that are connected to the same Wi-Fi router. I have written a small project containing a library with a shared variable, and two VIs, one which writes a value to it and one which reads it. After deploying the shared variable library from each of the computers I have tried to use the Distributed System Manager to check that the variable sharing is working properly, but it isn't. From computer A I can see the shared variables from computers A, B and C, but computers B and C can only see their own shared variables (see attached images). As long as a computer can see a variable I can write and read from it as expected using the write and read VIs.

It seems as if something is preventing computers B and C from receiving.

As suggested here (https://zone.ni.com/reference/en-XX/help/371361R-01/lvhowto/psp_firewall/), I have opened the following ports in the firewalls of each computer: TCP 2343, 59110-59115 and UDP 2343, 6000-6010, 5000-5010, and I have changed the router configuration to trigger ports TCP 2343, 59110-59115 and UDP 2343 (although I must admit I don't have a very good idea of how port triggering works or how to set it up properly). I have allowed the files mentioned here (https://knowledge.ni.com/KnowledgeArticleDetails?id=kA03q000000YIKqCAO&l=en-GB) as firewall exceptions in all three computers. I have also tried to disable the firewalls altogether, but it made no difference.

The three computers are running LabVIEW 18.

What may I be doing wrong?

[altenbach]

I assume that all are on the same subnet, so router configuration is probably not an issues. (Port triggering is certainly wrong, so get rid of that!).

What are the IP addresses and netmasks of all three computers?

[Sabier]

Hi altenbach. Thanks a lot for the quick reply. I will get rid of the port triggering and see if it makes any difference. The IP addresses and subnet masks are:

Computer A (cslp019717):

IPv4 Address: 192.168.0.162
Subnet Mask: 255.255.255.0

Computer B (CSSD016543):

IPv4 Address: 192.168.0.136

Subnet Mask: 255.255.255.0

Computer C (CSSD016546):

IPv4 Address: 192.168.0.230
Subnet Mask: 255.255.255.0

[Sabier]

I disabled the port triggering on the router and it made no difference, which I guess is good because it means I didn't need it in the first place 🙂

Any further ideas as to what may be going wrong? Do the IP addresses and subnet masks shine any light on the issue?

[altenbach]

So, all devices are on the same subnet and some see each other and some don't.

Can all ping each other?

What kind of wireless router is this? (some devices, e.g. intended for coffeeshops, prevent bridging between wifi devices for security)

How is access control configures on each PC?

Which computer (A, B, or C) is hosting the variable server?

[Sabier]

Until 20 minutes ago pinging between devices worked like so:

A could ping B, but not C

B couldn't ping anyone

C could ping B, but not A

Everyone could ping the router

Now I have switched on Windows' "network discovery" in all computers, and they can all ping each other. I'm not sure if this is related to the shared variable engine though, because it made no difference in terms of which shared variables can each computer see.

I don't know what kind of router I am using, it's definitely not intended for coffeeshops though. If it means anything to you it's a tp-link Archer AX6000 (https://www.tp-link.com/us/home-networking/wifi-router/archer-ax6000/). It has a ton of configuration options, and I must admit I don't understand half of them...

Regarding access control configuration, I am not really sure what you are referring to. As I mentioned on my first post I have opened several ports in the firewalls and included some executables as firewall exceptions, and just now allowed network discovery. I have tried setting the network to public, and to private, and enabled and disabled all the firewalls, but none of these made a difference. I am pretty sure I am looking in the wrong place (:

As for which computer is hosting, if I understand it correctly, whichever computer deploys a shared variable library will become a host for it. Is this correct? If this is the case then each of the computers is hosting a local variable, and I am checking with the other ones whether they can see it or not. If this is not how it works, then how can I decide which of the three is the variable server?

Many thanks in advance.

[Sabier]

Just a (sad) update: I still haven't been able to make this work.

Last thing I tried was to adjust the internet adapter priorities as suggested here (https://knowledge.ni.com/KnowledgeArticleDetails?id=kA00Z0000019MrxSAE&l=en-GB) but it didn't fix the issue.

Any further help would be very much appreciated.