For each server containing a RabbitMQ installation: navigate to C:\Users\Current User\.erlang.cookie and C:\Windows\.erlang.cookie. Set the value of the cookie to the RabbitMQNetworkName from DocGenSvcHost.exe.config; for example: WKFS_DocGenServicesStaging for example for the staging server. You can locate this in the Document Generation Services web.config or the Transforms.xml for your environment.
Stop and start the RabbitMQ service on each server.
To verify the clustering is configured properly, access the Management Application at http://localhost:15672/.