Enabling, disabling, reconfiguring, and monitoring

The DB Query resource adaptor supports management procedures to enable, disable, reconfigure, and monitor datasources.

Administratively enabling or disable a datasource

The profile attribute AdminEnable can be used to disable a configured datasource. If this attribute is set to false using a management interface (such as the Rhino command-line console), then the data source will be treated as though it is not available. The profile is polled for a change to this attribute with a period specified by attribute ProfilePollTime in the main DbQueryConfigProfile profile.

Reconfiguring datasources

Most aspects of datasource configuration can be modified while a datasource has been administratively disabled. When the datasource is re-enabled, the actual DataSource implementation class will be re-instantiated and reconfigured according to the new profile values.

Enabling or disabling tracing

The DB Query Resource Adaptor has several tracers that behave in the usual way, and whose trace levels can be modified using the Rhino management tools.

There is one special case. The trace level of the tracer dsm.driver determines whether or not setLogWriter() will be called on the DataSource class. If JDBC driver tracing is required, this tracer’s (or a parent’s) trace level should be set to FINEST. If JDBC driver tracing is no longer required, this tracer’s trace level should be unset.

Tracing can affect performance
  • The level check of this special tracer is made only once, when the datasource instance is created. A datasource instance may be created by either activating a resource adaptor entity or by administratively enabling the datasource (as described above).

  • If the tracer level is unset or set to a level other than FINEST, the tracing will be filtered by that trace level as usual; but the LogWriter will still be set on the driver, generating trace messages which are not displayed. This will have a performance impact.

  • If JDBC driver tracing is no longer needed, the tracer level should be unset or changed, and then the datasource forced to be re-instantiated by deactivating and activating the resource adaptor, or you can administratively disable then enable the datasource.

Previous page Next page