Client Plugins are not displayed - "Error: Provider 'NVBUPit' failed" (4038624)

Jobs for a client will fail with “Job manager lost message channel unexpectedly”.

When browsing the client plugins from "Manage Clients" or through a "Backup Selection", a spinning wheel shows up and may appear to hang. It may return a "Error: Provider 'NVBUPit' failed" error.

The “Check Access” and “Firewall Test” will complete successfully for the affected client.

If NetVault is uninstalled on the client and reinstalled as a NetVault Server, then it can browse its own plugins. However, while still as a server, if it’s added to another server the same would happen.

Looking at the trace logs a similar content may be found:

nvwsworker AAAA (Server)
===================
4 MESSAGE :05232 1080   0 004738.520465 Send 'CORE_PLG_GET_CLIENT_PROPERTIES_SCREEN_MSG' (2147) to NetVault:BBBB
2 WSPROV  :05232 5346   0 004738.521123 Short timeout of 30 seconds
0 WSPROV  :05232 3789   0 004808.523072 Failed to wait for reply from coreplugin

Cli Proxy BBBB (Server)
==============
4 MESSAGE :18896 1080   0 004738.521131 Send 'CORE_PLG_GET_CLIENT_PROPERTIES_SCREEN_MSG' (2147) to Cyborg:CCC

nvcoreplg CCC (client)
=============
4 MESSAGE :88561 1080   0 004738.575166 Send 'PLUGIN_DISPLAY_DISPOSABLE_SCREEN_MSG' (1717) to NetVault:BBBB

From the above, in essence we’re seeing that:

1.      nvwsworker sends 'CORE_PLG_GET_CLIENT_PROPERTIES_SCREEN_MSG' to cliproxy BBBB

2.      Which sends CORE_PLG_GET_CLIENT_PROPERTIES_SCREEN_MSG to nvcoreplg on the client

3.      In the meantime nvwsworker times out

If a wireshark or tcpdump capture is done on the client. Looking through the packets, there’d a be sequence where the client is trying to send the installed plugins info and retransmitting it a couple of times before issuing a TCP_RST. This can be found several times.