Hi all 
I am running into a really frustrating problem which I have tried in vain to troubleshoot for about a fortnight now, so would really appreciate some pointers on what to try next. Essentially my issue is as follows:
I have built Paraview v5.12.0 using superbuild on a a shared workstation and on a compute cluster. Both installations generally work fine, however we have a couple of custom readers in use (call them Reader A and Reader B), both of which are used to visualize file types which are based on HDF5.
There are no issues when either of these readers are used on the client or the server in isolation. We have a test suite which runs a series of .py tests using pvserver on the client side plus a host of XML tests for the GUI, which produce images that are compared with existing baselines, and all of them pass. Similarly, on the server side, we run the same .py tests and they all pass also.
However, when I attempt to run Paraview in client/server mode, attempting to open a file with Reader A will cause the server to disconnect immediately with no error messages or logging whatsoever, except for a pop-up informing the user of the disconnect and presenting the option to save the state. Reader B is fine and works as expected. Perhaps most confusingly however, is that if one opens a file with Reader B first, and then opens a file with Reader A, it works as expected and the server does not disconnect.
I have tried having both readers loaded automatically on both the client and the server side by including them in /bin/plugins. I have tried having neither loaded automatically by storing them with the other plugins under the /lib/paraview-5.12/plugins directory, and loading them manually. I have tried every combination of the two. I have rebuilt them several times to try and ensure they share dependencies to the greatest degree possible. I have tried building them in debug mode, but I didn’t manage to get any logs out of them. The only error logs I have to go on are that sometimes (not always) when I try to save the paraview state following the disconnect, I get a series of socket errors, beginning with:
vtkSMProxy.cxx:2176 ERR| vtkSMProxy (0x5b43ce0): Try to load a state on a proxy which has a different ID(17828 != 0)
However I suspect this is due to the server being disconnected, rather than the cause of the disconnect (though I am more than happy to be corrected).
I am utterly at a loss as to how to try and troubleshoot this. Any pointers would be welcome.
Thanks,
James