"Find Systems.vi" cannot find cRIO terminals across VLAN.

[JeremyZheng]

I have encountered a problem. I have multiple cRIO terminals distributed in a large network with different subnets, such as 192.168.0.X, 192.168.1.X, 192.168.3.X, etc. I use a computer (IP address 192.168.0.100) to manage all the terminals. I can view each terminal through MAX installed on the computer. Now I want to operate the terminals through a LabVIEW application. I found a problem that the Find Systems.vi can only query the terminals in the current subnet, so I cannot operate other terminals. I think the mechanism for finding terminals should be the same as MAX, so this may be a bug. Do you have any solutions?

[ZYOng]

You are right that NI MAX uses NI System Configuration API. However, the NI SysCfg API cannot detect a new remote target on a different subnet. The remote targets from the different subnets are listed in your NI MAX because you have added their IP address manually previously. If you remove all of them or try to browse from a different host PC that does not have them added, you will find out that NI MAX is not able to list them.

[rolfk]

In order to "find" systems the SystemControl API needs to use broadcast messages. Any reasonably configured router nowadays will by default drop broadcast messages and not forward them to other subnets, simply because not doing so could very well overload your entire network eventually. A managed router can be configured to forward broadcast messages to specific other subnets but that is something that needs to be done by the according IT administrator!