An agent blackout or global blackout is configured during a maintenance window; no alarms are received while the blackout is active but once it ends many Credential Management Event alarms fire and get cleared automatically.
Credential alarms are for WinRM connections but agents are able to establish DCOM connections; for example:
Fatal Severity
>> Failure: Cannot establish connection to hostname.yourdomain.com: WinRM request to https://hostname.yourdomain.com:5986/wsman failed: [Caused by: ConnectException <Connection timed out: no further information>]
>> Failure: Cannot establish connection to hostname.yourdomain.com: WinRM request to https://hostname.yourdomain.com:443/wsman failed: [Caused by: ConnectException <Connection timed out: no further information>]
>> Failure: Cannot establish connection to hostname.yourdomain.com: WinRM request to http://hostname.yourdomain.com:5985/wsman failed: received HTTP/401 - credentials rejected
>> Failure: Cannot establish connection to hostname.yourdomain.com: WinRM request to https://hostname.yourdomain.com:5986/wsman failed: [Caused by: ConnectException <Connection timed out: no further information>]
>> Failure: Cannot establish connection to hostname.yourdomain.com: WinRM request to http://hostname.yourdomain.com:80/wsman failed: [Caused by: ConnectException <Connection timed out: no further information>]
Transient connection failures while agents attempt to establish connections using different connection methods or credential types once a blackout is over.
WORKAROUND
Disable credential alarms.
For more information refer to How to disable Credential Management Event alarms (4252496).
STATUS
Enhancement request FOG-10409 to delay the creation of credential alarms has been included in the 8.0.0 and higher releases of the Foglight Management Server.
