You can test a JDBC connection pool for usability in one of these ways:
In the Admin Console, open the Resources component, open the JDBC component, select Connection Pools, and select the connection pool you want to test. Then select the Ping button in the top right corner of the page. For details, click the Help button in the Admin Console.
Use the asadmin ping-connection-pool command. For details, see the Sun GlassFish Enterprise Server v2.1.1 Reference Manual.
Both these commands fail and display an error message unless they successfully connect to the connection pool.
For information about how to tune a connection pool, see the Sun GlassFish Enterprise Server v2.1.1 Performance Tuning Guide.