Getting SQL connection failures pretty often

[shadyabhi]

My log file is filled with many SQL communication failures like:

Feb 1, 2013 9:01:50 AM com.openexchange.log.internal.LoggerTask call
SEVERE: Logged at: com.openexchange.exception.OXException.log(OXException.java:544)
 com.openexchange.ajp13.remoteAddress=1.1.1.1
 com.openexchange.ajp13.remotePort=39177
 com.openexchange.database.schema=oxdatabase_7
 com.openexchange.session.clientId=com.openexchange.ox.gui.dhtml
 com.openexchange.session.contextId=315
 com.openexchange.session.userId=4

 USR-0005 Categories=SERVICE_DOWN Message='Cannot get database connection.' exceptionID=-622917891-13006
USR-0005 Categories=SERVICE_DOWN Message='Cannot get database connection.' exceptionID=-622917891-13006
        at com.openexchange.exception.OXExceptionFactory.create(OXExceptionFactory.java:156)
        at com.openexchange.groupware.ldap.LdapExceptionCode.create(LdapExceptionCode.java:164)
        at com.openexchange.groupware.ldap.RdbUserStorage.getUser(RdbUserStorage.java:277)
        at com.openexchange.groupware.ldap.UserFactory.load(UserFactory.java:83)
        at com.openexchange.groupware.ldap.UserFactory.load(UserFactory.java:59)
        at com.openexchange.caching.dynamic.Refresher.refresh(Refresher.java:289)
        at com.openexchange.caching.dynamic.Refresher.refresh(Refresher.java:190)
        at com.openexchange.caching.dynamic.Refresher.refresh(Refresher.java:128)
        at com.openexchange.groupware.ldap.UserReloader.<init>(UserReloader.java:84)
        at com.openexchange.groupware.ldap.CachingUserStorage.createProxy(CachingUserStorage.java:176)
        at com.openexchange.groupware.ldap.CachingUserStorage.getUser(CachingUserStorage.java:171)
        at com.openexchange.ajax.SessionServlet.getSession(SessionServlet.java:588)
        at com.openexchange.ajax.SessionServlet.getSession(SessionServlet.java:547)
        at com.openexchange.ajax.SessionServlet.initializeSession(SessionServlet.java:218)
        at com.openexchange.ajax.SessionServlet.service(SessionServlet.java:276)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)
        at com.openexchange.ajp13.coyote.AjpProcessor.process(AjpProcessor.java:908)
        at com.openexchange.ajp13.coyote.sockethandler.CoyoteTask.call(CoyoteTask.java:185)
        at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
        at java.util.concurrent.FutureTask.run(FutureTask.java:138)
        at com.openexchange.threadpool.internal.CustomThreadPoolExecutor$Worker.runTask(CustomThreadPoolExecutor.java:798)
        at com.openexchange.threadpool.internal.CustomThreadPoolExecutor$Worker.run(CustomThreadPoolExecutor.java:825)
        at java.lang.Thread.run(Thread.java:662)
Caused by: DBP-0006 Categories=ERROR Message='Problem with executing SQL: Communications link failure



USR-0005 Categories=SERVICE_DOWN Message='Cannot get database connection.' exceptionID=-622917891-13006
USR-0005 Categories=SERVICE_DOWN Message='Cannot get database connection.' exceptionID=-622917891-13006
        at com.openexchange.exception.OXExceptionFactory.create(OXExceptionFactory.java:156)
        at com.openexchange.groupware.ldap.LdapExceptionCode.create(LdapExceptionCode.java:164)
        at com.openexchange.groupware.ldap.RdbUserStorage.getUser(RdbUserStorage.java:277)
        at com.openexchange.groupware.ldap.UserFactory.load(UserFactory.java:83)
        at com.openexchange.groupware.ldap.UserFactory.load(UserFactory.java:59)
        at com.openexchange.caching.dynamic.Refresher.refresh(Refresher.java:289)
        at com.openexchange.caching.dynamic.Refresher.refresh(Refresher.java:190)
        at com.openexchange.caching.dynamic.Refresher.refresh(Refresher.java:128)
        at com.openexchange.groupware.ldap.UserReloader.<init>(UserReloader.java:84)
        at com.openexchange.groupware.ldap.CachingUserStorage.createProxy(CachingUserStorage.java:176)
        at com.openexchange.groupware.ldap.CachingUserStorage.getUser(CachingUserStorage.java:171)
        at com.openexchange.ajax.SessionServlet.getSession(SessionServlet.java:588)
        at com.openexchange.ajax.SessionServlet.getSession(SessionServlet.java:547)
        at com.openexchange.ajax.SessionServlet.initializeSession(SessionServlet.java:218)
        at com.openexchange.ajax.SessionServlet.service(SessionServlet.java:276)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)
        at com.openexchange.ajp13.coyote.AjpProcessor.process(AjpProcessor.java:908)
        at com.openexchange.ajp13.coyote.sockethandler.CoyoteTask.call(CoyoteTask.java:185)
        at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
        at java.util.concurrent.FutureTask.run(FutureTask.java:138)
        at com.openexchange.threadpool.internal.CustomThreadPoolExecutor$Worker.runTask(CustomThreadPoolExecutor.java:798)
        at com.openexchange.threadpool.internal.CustomThreadPoolExecutor$Worker.run(CustomThreadPoolExecutor.java:825)
        at java.lang.Thread.run(Thread.java:662)
Caused by: DBP-0006 Categories=ERROR Message='Problem with executing SQL: Communications link failure

The last packet successfully received from the server was 58,227 milliseconds ago.  The last packet sent successfully to the server was 0 milliseconds ago.' exceptionID=-622917891-13005
        at com.openexchange.database.DBPoolingExceptionCodes.create(DBPoolingExceptionCodes.java:224)
        at com.openexchange.database.internal.ContextDatabaseLifeCycle.loadPoolData(ContextDatabaseLifeCycle.java:182)
        at com.openexchange.database.internal.ContextDatabaseLifeCycle.create(ContextDatabaseLifeCycle.java:102)
        at com.openexchange.database.internal.Pools.getPool(Pools.java:108)
        at com.openexchange.database.internal.ReplicationMonitor$1.get(ReplicationMonitor.java:101)
        at com.openexchange.database.internal.ReplicationMonitor.checkActualAndFallback(ReplicationMonitor.java:155)
        at com.openexchange.database.internal.ReplicationMonitor.checkActualAndFallback(ReplicationMonitor.java:145)
        at com.openexchange.database.internal.DatabaseServiceImpl.get(DatabaseServiceImpl.java:95)
        at com.openexchange.database.internal.DatabaseServiceImpl.getReadOnly(DatabaseServiceImpl.java:156)
        at com.openexchange.databaseold.Database.get(Database.java:115)
        at com.openexchange.server.impl.DBPool.pickup(DBPool.java:68)
        at com.openexchange.groupware.ldap.RdbUserStorage.getUser(RdbUserStorage.java:275)
        ... 20 more
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

The last packet successfully received from the server was 58,227 milliseconds ago.  The last packet sent successfully to the server was 0 milliseconds ago.
        at sun.reflect.GeneratedConstructorAccessor88.newInstance(Unknown Source)
        at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
        at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
        at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
        at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1117)
        at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3589)
        at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3478)
        at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4019)
        at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2490)
        at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2651)
        at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2734)
        at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2155)
        at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:2322)
        at com.openexchange.database.internal.ContextDatabaseLifeCycle.loadPoolData(ContextDatabaseLifeCycle.java:166)
        ... 30 more
Caused by: java.io.EOFException: Can not read response from server. Expected to read 4 bytes, read 0 bytes before connection was unexpectedly lost.
        at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:3039)
        at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3489)
        ... 38 more

This is a pretty serious error because this error happens user tries to login & everything goes fine in the second run.

Searching on google said that it's because of mysql closing the idle connections. Can anyone help me in solving this?

My configdb.properties looks like: http://sprunge.us/bBFH

[Martin Heiland]

Are you sure "readUrl=jdbc:mysql://localhost:13306/configdb" is correct? Or perhaps a typo?