PE 3.7 Console Live Management: Received frame of type 'ERROR' expected 'MESSAGE'
We have a "split installation" of PE 3.7. That is, puppetmaster, puppetdb, and puppetdashboard are on separate machines. pe-activemq is installed on the puppetmaster. 'mco ping' (running from puppetmaster) is able to find all three nodes. With the console, click on "Live Management", shows an error message:
An error occurred while the server was looking for active nodes. For more information, check /var/log/pe-puppet-dashboard/live-management.log.
The error message in /var/log/pe-puppet-dashboard/live-management.log is:
[2014-12-14 07:50:39.600 UTC] ERROR [USER: admin] [SESSION: b47ddfcd0462a070b9d7f8b9e6214f5d] Received frame of type 'ERROR' expected 'MESSAGE'
What could be the root cause?