About Instances
This section explains how Azul Intelligence Cloud detects and collects information about instances.
Instance States
The state of an instance indicates whether the instance is running, offline, or has been terminated. The instance state is detected based on the events that CRS reports to Azul Intelligence Cloud during instance’s lifetime. In the Web UI, the state of an instance is always considered as of now, and is indicated by the following labels:
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RUNNING: Indicates that the instance is running. The instance sends events regularly. -
TERMINATED: Indicates that the instance was terminated. A termination event has been received. -
OFFLINE: The service has not heard from the instance for 5 minutes. This can happen when the instance terminated abruptly and didn’t send a termination event, or when the instance lost connection to the service.
The state in the service may differ from the actual state of the instance. For example:
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An instance is started but CRS is not enabled. In this case, the actual instance continues to run but it is not registered in the service.
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An instance was connected to the service, but lost the connection at some point. In this case, the actual instance continues to run, but the service sets the state to "offline" after a predefined timeout.
What Information is Reported
The CRS (Connected Runtime Service) in the Azul JVM sends information about the instance and instance host environment to the Azul Intelligence Cloud service.
See What Info Is Transmitted Between Your System And Azul Intelligence Cloud for the full information.