Oracle® Enterprise Manager Oracle Database and Database-Related Metric Reference Manual 12c Release 1 (12.1.0.2.0) Part Number E25160-03 |
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PDF · Mobi · ePub |
You can use Enterprise Manager to manage Oracle Listener targets. From the Enterprise Manager Listener home page, you can monitor key metrics that can help determine the performance and availability of the listener and help you troubleshoot potential performance problems.
This metric is a container for a set of metrics that provide general information about the listener target. For more information, see the section on Listener Administration in the Oracle Database Net Services Administrator's Guide 10g Release 2 (10.2).
Alternative name for the listener. On the Metric Detail page, you can see the value of this metric only when you select one of the Real Time refresh options. The alias also appears on the Listener home page.
The following table shows how often the metric's value is collected.
Target Version | Collection Frequency |
---|---|
All Versions | Every 15 Minutes |
Derived from the STATUS command of the Listener Control Utility
Shows whether or not a password is required to run specific commands with the Listener Control Utility.
The following table shows how often the metric's value is collected.
Target Version | Collection Frequency |
---|---|
All Versions | Every 15 Minutes |
Derived from the STATUS command of the Listener Control Utility
Lists the System Identifiers (SIDs) for the services monitored by the listener
The following table shows how often the metric's value is collected.
Target Version | Collection Frequency |
---|---|
All Versions | Every 15 Minutes |
List of SIDs for the listener is stored in the listener.ora
configuration file
Indicates whether or not the listener can respond to queries from an SNMP-based network management system
The following table shows how often the metric's value is collected.
Target Version | Collection Frequency |
---|---|
All Versions | Every 15 Minutes |
Derived from the STATUS command of the Listener Control Utility
Represents the day and time when the listener was last started. On the Metric Detail page, you can see the value of this metric only when you select one of the Real Time refresh options. This metric also appears on the Enterprise Manager Listener home page.
The following table shows how often the metric's value is collected.
Target Version | Collection Frequency |
---|---|
All Versions | Every 15 Minutes |
Derived from the STATUS command of the Listener Control Utility
Displays the protocol, host, and port information for the listener. On the Metric Detail page, you can see the value of this metric only when you select one of the Real Time refresh options. The TNS address also appears on the Listener home page.
The following table shows how often the metric's value is collected.
Target Version | Collection Frequency |
---|---|
All Versions | Every 15 Minutes |
TNS address of the Listener is defined in the listener.ora
configuration file
Represents the level of tracing currently enabled for the listener. Tracing can be used to troubleshoot problems with the listener by saving additional information to the trace file. For more information about the trace levels you can set for the listener, see the information about the Listener Control Utility in the Oracle Database Net Services Reference Guide 10g Release 2 (10.2).
On the Metric Detail page, you can see the value of this metric only when you select one of the Real Time refresh options.
The following table shows how often the metric's value is collected.
Target Version | Collection Frequency |
---|---|
All Versions | Every 15 Minutes |
Derived from the STATUS command of the Listener Control Utility
Version of the listener software. On the Metric Detail page, you can see the value of this metric only when you select one of the Real Time refresh options. This metric also appears on the Enterprise Manager Listener home page.
The following table shows how often the metric's value is collected.
Target Version | Collection Frequency |
---|---|
All Versions | Every 15 Minutes |
Derived from the STATUS command of the Listener Control Utility
This metric is a container for a set of metrics that provide you with information about the number of connections supported by the Listener over a period of time. For more information, see the section on Listener Administration in the Oracle Database Net Services Administrator's Guide 10g Release 2 (10.2).
Number of connections established since the listener was last started
The following table shows how often the metric's value is collected.
Target Version | Collection Frequency |
---|---|
All Versions | Every 15 Minutes |
Derived from the SERVICES
command of the Listener Control Utility
If you are noticing experiencing performance issues with the database or other services supported by the listener, review the historical values of this metric to determine whether or not the performance problems are caused by excessive load on the listener or host.
Average number of connections per minute that were established with the listener
Derived from the Listener Control Utility
The following table shows how often the metric's value is collected.
Target Version | Collection Frequency |
---|---|
All Versions | Every 15 Minutes |
If you are noticing experiencing performance issues with the database or other services supported by the listener, review the historical values of this metric to determine whether or not the performance problems are caused by excessive load on the listener or host.
Number of connections to the listener that were refused. A connection can be refused for a variety of reasons, including situations where the database or other listener service is down, or if the connection timed out.
The following table shows how often the metric's value is collected.
Target Version | Collection Frequency |
---|---|
All Versions | Every 15 Minutes |
Derived from the SERVICES
command of the Listener Control Utility
If Enterprise Manager reports a high number of refused connections, check the availability and performance of the database or other services supported by the listener.
Average number of connections that were refused per minute
The following table shows how often the metric's value is collected.
Target Version | Collection Frequency |
---|---|
All Versions | Every 15 Minutes |
Derived from the Listener Control Utility
If Enterprise Manager reports a high number of refused connections, check the availability and performance of the database or other services supported by the listener.
This metric is a container for the Response and Status metrics that provide you with performance information about the Listener.
This metric represents the time (in milliseconds) that it takes for the Listener to respond to a network request (ping).
By default, this metric has a critical threshold of 100 and a warning threshold of 80. A critical alert is generated when the metric value exceeds the critical threshold value 1 time. A warning alert is generated when the metric value exceeds the warning threshold value 1 time. You can edit the value for a threshold as required.
By default, Enterprise Manager tests the value of this metric every 24 hours.
When an alert is generated, the alert text is:
Listener response to a TNS ping is %value% msecs
The value of this metric is derived using the TNSPING
command. For more information about the TNSPING
command, see the Oracle Database Net Services Administrator's Guide 10g Release 2 (10.2).
If the Listener response time consistently exceeds the threshold, users are likely experiencing performance issues while accessing the database or other services on this host. Use the Enterprise Manager Central Console to review other performance indicators, such as the overall health of your database and the response time of your hosts and Web Applications.
This metric returns a value of "1" if the Listener is up and running; it returns a 0 if the Listener is unavailable.
By default, this metric has a critical threshold of 0. A critical alert is generated when the metric value equals the critical threshold value 1 time. You can edit the value for a threshold as required.
By default, Enterprise Manager tests the value of this metric every 24 hours.
When an alert is generated, the alert text is:
The listener is down: %oraerr%.
This metric is derived from the STATUS
command in the Listener Control Utility. For more information, see the Oracle Database Net Services Administrator's Guide 10g Release 2 (10.2).
When the listener is down, users cannot access the database or other services on this host. Review the troubleshooting information in Oracle Database Net Services Administrator's Guide 10g Release 2 (10.2).
The TNSPING utility determines whether or not a service (for example, an Oracle database or any other service) on an Oracle Net network can be successfully reached. If you can connect successfully from a client to a server (or a server to another server) using the TNSPING utility, it displays an estimate of the round trip time (in milliseconds) to reach the Oracle Net service.
If it fails, it displays a message describing the error that occurred. This enables you to see the network error that is occurring without the overhead of a database connection.
The following table shows how often the metric's value is collected.
Table 8-1 Metric Summary Table
Target Version | Evaluation and Collection Frequency | Upload Frequency | Operator | Default Warning Threshold | Default Critical Threshold | Consecutive Number of Occurrences Preceding Notification | Alert Text |
---|---|---|---|---|---|---|---|
All Versions |
Every 5 Minutes |
After Every Sample |
> |
400 |
1000 |
- |
Listener response to a TNS ping is %value% msecs |
This metric is derived from the tnsping <TNS address>
command in the Listener Control Utility. For more information, see the Oracle Database Net Services Administrator's Guide 10g Release 2 (10.2).
When the listener is down, users cannot access the database or other services on this host. Review the troubleshooting information in Oracle Database Net Services Administrator's Guide 10g Release 2 (10.2).
This metric collects configuration data for listener, for example ports, protocol, host. It is computed using the lsnrctl status <listener Name>
command on all platforms.
This metric collects configuration data for the services registered to the listener (for example, service name, is sid, or service).
It is computed using the lsnrctl status <listener Name>
command on all platforms.
This metric performs incremental scanning of listener log files for security errors. These error codes are predefined and could be any of the following:
1169
1189
1190
12508
The following table shows how often the metric's value is collected.
Table 8-2 Metric Summary Table
Target Version | Evaluation and Collection Frequency | Upload Frequency | Operator | Default Warning Threshold | Default Critical Threshold | Consecutive Number of Occurrences Preceding Notification | Alert Text |
---|---|---|---|---|---|---|---|
All Versions |
Every 15 Minutes |
After Every Sample |
MATCH |
- |
*TNS* |
- |
<command causing security error>(<Error code generated>) .Please chk log for details. |