The report shows servers that has not send Processor (CPU) and memory performance data in the last 4 hours.
Note: This report excludes clusters (agent-less) from the query.
Possible causes for agents appearing on this report can be
1. problematic agent/unhealthy, stopped health service etc etc.
2. Performance counter corruption, perfmon shows numbers instead of names
3. Firewall between the agent and the management server
4. Server decommissioned – greyed out
1. Look at agents on *nix servers like Unix and Linux.
PM me if you are interested in the query or report.