Good morning!
I've been running into an intermittent problem with my database connections for authentication. It appears that periodically, the iSeries (DB2/400) that I connect to terminates all incoming ODBC/JDBC connections (one a week, apparently). What happens in my application is that users can no longer login after the connections have been dropped. The connection pool apparently doesn't try to re-initiate the connections after they've been dropped.
I see an exception in my logs regarding the connection being reset, then I see an exception relating to the pool being exhausted. I'm not entirely sure what the root cause of the problem here is - in theory, DBCP should recover gracefully when a connection is reset/dropped, right?
Here's the initial exception:
java.sql.SQLException: Communication link failure.(Connection was dropped unexpectedly.)
at com.ibm.as400.access.JDError.throwSQLException(JDError.java:365)
at com.ibm.as400.access.AS400JDBCConnection.send(AS400JDBCConnection.java(Compiled Code))
at com.ibm.as400.access.AS400JDBCConnection.send(AS400JDBCConnection.java(Inlined Compiled Code))
at com.ibm.as400.access.AS400JDBCStatement.syncRPB(AS400JDBCStatement.java(Compiled Code))
at com.ibm.as400.access.AS400JDBCStatement.commonPrepare(AS400JDBCStatement.java(Compiled Code))
at com.ibm.as400.access.AS400JDBCPreparedStatement.<init>(AS400JDBCPreparedStatement.java(Compiled Code))
at com.ibm.as400.access.AS400JDBCConnection.prepareStatement(AS400JDBCConnection.java(Compiled Code))
at com.ibm.as400.access.AS400JDBCConnection.prepareStatement(AS400JDBCConnection.java(Compiled Code))
at org.apache.commons.dbcp.DelegatingConnection.prepareStatement(DelegatingConnection.java(Compiled Code))
at org.apache.commons.dbcp.PoolingDataSource$PoolGuardConnectionWrapper.prepareStatement(PoolingDataSource.java(Compiled Code))
at org.apache.catalina.realm.DataSourceRealm.credentials(DataSourceRealm.java:460)
[snip]
Here's the next one:
2004-12-06 04:39:21 DataSourceRealm[]: Exception performing authentication
org.apache.commons.dbcp.SQLNestedException: Cannot get a connection, pool exhausted
at org.apache.commons.dbcp.PoolingDataSource.getConnection(PoolingDataSource.java(Compiled Code))
at org.apache.commons.dbcp.BasicDataSource.getConnection(BasicDataSource.java(Compiled Code))
at org.apache.catalina.realm.DataSourceRealm.open(DataSourceRealm.java:438)
at org.apache.catalina.realm.DataSourceRealm.authenticate(DataSourceRealm.java:277)
[snip]
So, what I've done now to see if it helps matters any, is specify the AS400's own connection pool factory in my JNDI definition, like so:
<parameter>
<name>factory></name>
<value>com.ibm.as400.access.AS400JDBCConnectionPoolDataSource</value>
</parameter>
Both Tomcat's form authentication as well as my application (through iBATiS) use this JNDI DataSource for connections.
Can anyone shed more light on what the root cause of the problem is here? Should DBCP gracefully recover?
Regards, Brice Ruth
-- Brice Ruth, Sr. IT Analyst Fiskars Brands Inc http://www.fiskarsbrands.com/
--------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
