Following the installation of the Modbus plugin or a third-party software on the server, the plugin role is yellow and you receive the following message: Internal communication error. Connection to gateway has been lost.
Cause
The gateway of the plugin is unable to communicate with RabbitMQ, or RabbitMQ is unreachable.
Solution 1: In Windows, set the HOMEDRIVE environment variable to the drive on which the plugin is installed, and then restart the server.
Solution 2: Disable all network interfaces other than the main network interface of the server and restart server.
Solution 3: Verify that Microsoft Visual C++ 2013 x86 Redistributable is present on the server. If not, install it, and then restart the server.
Solution 4: Verify that RabbitMQ ports are not in use.
Solution 5: For the SNMP plugin, verify that port 162 is not in use by the server.