Managed Solr users sometimes see an alarming red message in the list of servers of the Deployment Details page:
The Pulse Agent warning is usually temporary, and will resolve itself within a few minutes. The process that reports performance statistics to SearchStax has stopped responding. It appears briefly after restarting a node. It does not always mean that the Solr service has been interrupted.
There is one situation where the message is more serious. If Solr runs out of memory, it may stop the Pulse Agent to free up resources. Check the Pulse graphs for that server to see if memory usage is very high. If so, you can stop/restart the node to clear the problem.
If the “Pulse Agent is Down” message appears too frequently or cannot be cleared, contact the SearchStax Support Desk.