Checking Host Heartbeats
One way to check whether all the Agents are running is to look at the time since their last heartbeat. You can do this by clicking the Hosts tab where you can see a list of all the hosts along with the value of their Last Heartbeat.
By default, every Agent must heartbeat successfully every 15 seconds. A recent value for the Last Heartbeat means that the Server and Agents are communicating successfully.