Error :: Communications link failure due to underlying exception

[Mr. Ram]

Current now, I am working on one struts application. The application working under Tomcat webserver and MySQL.

Sometimes, the tomcat console displaying the following error for this application:-

Communications link failure due to underlying exception:
** BEGIN NESTED EXCEPTION **
java.net.SocketException
MESSAGE: Software caused connection abort: recv failed
STACKTRACE: java.net.SocketException: Software caused connection abort: recv failed

But, the application is working fine.

[Khalid Ali]

post a full stack trace if thats possible...

[Mr. Ram]

Tue Feb 28 13:40:27 IST 2006 :: No ManagedConnections available within configured blocking timeout ( 50000 [ms] ); - nested throwable: (javax.resource.ResourceException: No ManagedConnections available within configured blocking timeout ( 50000 [ms] ))

Thu Feb 16 12:56:09 IST 2006 :: Connection to the database could not be established; nested exception is: security.exception.SecurityDAOException: Connection to the database could not be established

Tue Feb 28 19:21:40 IST 2006 :: DataBase Exception occured while transacting with DB

Tue Feb 28 19:21:44 IST 2006 :: populatesessionBean=Could not create connection; - nested throwable: (java.sql.SQLException: Data source rejected establishment of connection, message from server: "Too many connections"); - nested throwable : (org.jboss.resource.JBossResourceException: Could not create connection; - nested throwable: (java.sql.SQLException: Data source rejected establishment of connection, message from server: "Too many connections"))


I thought, JBoss unable to remove the Abandoned Connections for this specific applications.

[Khalid Ali]

I thought, JBoss unable to remove the Abandoned Connections for this specific applications.

That makes sense, however since I have never worked with JBOss so not sure.
This is what I would do the first.
Make suer that when you perform query you close a connection once you are done (which means implement finally block with try catch) and close open conns in the finally block. To me seems like a design flaw....

[Mr. Ram]

I have faced same problem in Tomcat. At that time, I have added the following tags in DB config.xml file without updating application code.

<!-- To configure a DBCP DataSource so that abandoned dB connections are removed and recycled add the following paramater to the ResourceParams configuration for your DBCP DataSource Resource: -->

<parameter>
<name>removeAbandoned</name>
<value>true</value>
</parameter>

<!--Use the removeAbandonedTimeout parameter to set the number of
seconds a dB connection has been idle before it is considered abandoned. -->

<parameter>
<name>removeAbandonedTimeout</name>
<value>60</value>
</parameter>

<!--The logAbandoned parameter can be set to true if you want DBCP to log a stack trace of the code which abandoned the dB connection resources -->

<parameter>
<name>logAbandoned</name>
<value>true</value>
</parameter>

Now, I am expecting the similar tags to add to mysql-ds.xml file in case of JBOSS without updating application code. Bz, we had only ear file.

[Khalid Ali]

well that means that you will have to talk JBoss people and see which format of such configuration that use(af at all)...sounds like tomcat solution was server specific

[Mr. Ram]

Created JIRA Issue: http://jira.jboss.com/jira/browse/JBCACHE-346

[Mr. Ram]

Error :: Communications link failure due to underlying exception

This is because :
MySQL closes conections after 8 hours of inactivity.
autoReconnect=true