D Overview of Target Availability States
The following sections summarize available states and how to set real-time target status updates.
D.1 Target Availability State Changes
Enterprise Manager displays a comprehensive array of target availability statuses in the form of informational icons. Various Cloud Control console pages display these icons to indicate the current status of targets in the repository.
The following table contains all available target availability status icons and their meaning.
| Icon | Availability State | Description |
|---|---|---|
| N/A | N/A | Target availability state does not apply. |
 |
Down | Target is down.
The target may be unreachable due to the fact that the Agent is down. If the Agent was brought down as part of planned maintenance, consider creating a blackout on the Agent. |
 |
Up | Target is up. |
 |
Availability Evaluation Error | An error occurred while attempting to determine target availability status. A target availability evaluation error can be caused by metric collection errors, the Agent being unreachable, or network problems. |
 |
Agent Down | The Agent monitoring the target is down.
If an Agent was brought down in error it should be restarted. If Agent was brought down as part of planned maintenance, consider creating a blackout on the Agent. |
 |
Agent Down, Target Up | The Agent monitoring the target is down, however, the target is currently up but not monitored.
To troubleshoot, go to the Agent homepage and run the Symptom Analysis tool located next to the Status field. |
 |
Agent Unreachable | The Agent is not reachable. Specifically, the Oracle Management Service (OMS) cannot communicate with the Agent.
An Agent is generally unreachable when it is down, when it is blocked by the OMS, or when the Management Agent host is down. A Management Agent may also be unreachable due to network problems or certain other issues. |
 |
Agent Unreachable (Under Migration) | The Agent is unreachable because it is in the process of being migration. |
 |
Agent Unreachable (Cannot Write to File System) | The Agent cannot write to the file system.
Check the Agent file system for accessibility. To troubleshoot problems, navigate to the Agent home page from the Enterprise Manager console and run the Symptom Analysis tool (located next to the Status field). |
 |
Agent Unreachable (Collections Disabled) | Agent metric collection has been disabled.
Check that the Agent can upload to the OMS. To troubleshoot problems, navigate to the Agent home page from the Enterprise Manager console and run the Symptom Analysis tool (located next to the Status field). |
 |
Agent Unreachable (Disk Full) | The Agent file system is full.
Check the Agent file system for available space. To troubleshoot problems, navigate to the Agent home page from the Enterprise Manager console and run the Symptom Analysis tool (located next to the Status field). |
 |
Agent Unreachable (Post Blackout) | The Agent is unreachable because the first alert condition has not yet occurred since the blackout period ended. |
 |
Agent Blocked (Blocked Manually) | The Agent has been blocked manually.
Unblock the Agent. |
 |
Agent Blocked (Plug-in Mismatch) | The Agent has been blocked due to a plug-in mismatch.
If the Agent has been restored from a backup, perform an Agent Resync. |
 |
Agent Blocked (Bounce Counter Mismatch) | The Agent has been blocked due to Bounce Counter mismatch.
If the Agent has been restored from a backup, perform an Agent Resync. |
 |
Agent Unreachable (Agent Misconfigured) | The Agent is configured for communication with a different OMS.
Check the Agent configuration to ensure the Agent is communicating with the correct OMS. |
 |
Agent Unreachable (Communication Broken) | The Agent is unreachable due to a communication break between the Agent and the OMS. |
 |
Blackout | The target is currently blacked out. |
 |
Status Pending | The target status is currently unknown. |
 |
Status Pending (Target Addition in Progress) | The target status is currently unknown. Target addition is in progress. |
 |
Status Pending (Post Blackout) | The target status is currently unknown. Blackout has recently ended on this target and Availability Status is pending. |
 |
Status Pending (Post Metric Error) | A metric error has recently ended on the target and Availability Status is pending. To troubleshoot, refer to My Oracle Support article Enterprise Manager 12c: How to run the "Targets Status Diagnostics Report" to Troubleshoot Target Status Availability Issues (up, down, metric collection error, pending, unreachable) for all Targets (Doc ID 1546575.1). |
D.2 Target Status Change Updates
Enterprise Manager can automatically update target information for specific target context UI pages without having to refresh the browser page or wait for the status change to be detected by the Response metric, where the collection interval delay may take anywhere from a few tenths of a second to a few minutes.
A target context page displays information about a particular target. It has a context header at the top showing information such as target name, target type, target status, or target menu.
Status change updates are available for the following target types:
-
Agent
-
Host
-
Database Instance (Single Instance Database Only)
-
Application Deployment
-
WebLogic Server
As mentioned earlier, this feature allows target context pages to be updated automatically when that target's status changes (from up to down, for example). By default, automatic status change update is off. You can toggle this feature on and off using the oracle.sysman.core.uifwk.realTimeUIEnabled OMS property.
To enable status change updates, run the following emctl command:
emctl set property -name oracle.sysman.core.uifwk.realTimeUIEnabled -value true