Tomcat6 can't connect to MySql (The driver has not received any packets from the server)

i'm running an Apache Tomcat 6.0.20 / MySQL 5.1.37-lubuntu / sun-java6-jdk /sun-java6-jre / sun-java6-bin on my local machine using Ubuntu 9.10 as OS. I'm trying to get a simple DB-query example running for 2 days now, but i still get this Exception: ``` org.apache.jasper.JasperException: javax.servlet.ServletException: javax.servlet.jsp.JspException: Unable to get connection, DataSource invalid: "org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Communications link failure The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.)" org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:522) org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:398) org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:342) org.apache.jasper.servlet.JspServlet.service(JspServlet.java:267) javax.servlet.http.HttpServlet.service(HttpServlet.java:717) root cause javax.servlet.ServletException: javax.servlet.jsp.JspException: Unable to get connection, DataSource invalid: "org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Communications link failure The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.)" org.apache.jasper.runtime.PageContextImpl.doHandlePageException(PageContextImpl.java:862) org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImpl.java:791) org.apache.jsp.index_jsp._jspService(index_jsp.java:104) org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70) javax.servlet.http.HttpServlet.service(HttpServlet.java:717) org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:374) org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:342) org.apache.jasper.servlet.JspServlet.service(JspServlet.java:267) javax.servlet.http.HttpServlet.service(HttpServlet.java:717) root cause javax.servlet.jsp.JspException: Unable to get connection, DataSource invalid: "org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Communications link failure The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.)" org.apache.taglibs.standard.tag.common.sql.QueryTagSupport.getConnection(QueryTagSupport.java:285) org.apache.taglibs.standard.tag.common.sql.QueryTagSupport.doStartTag(QueryTagSupport.java:168) org.apache.jsp.index_jsp._jspx_meth_sql_005fquery_005f0(index_jsp.java:274) org.apache.jsp.index_jsp._jspx_meth_c_005fotherwise_005f0(index_jsp.java:216) org.apache.jsp.index_jsp._jspx_meth_c_005fchoose_005f0(index_jsp.java:130) org.apache.jsp.index_jsp._jspService(index_jsp.java:93) org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70) javax.servlet.http.HttpServlet.service(HttpServlet.java:717) org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:374) org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:342) org.apache.jasper.servlet.JspServlet.service(JspServlet.java:267) javax.servlet.http.HttpServlet.service(HttpServlet.java:717) ``` my web.xml looks like this : ``` <?xml version="1.0" encoding="utf-8"?> <web-app xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" version="2.5"> <resource-ref> <description>DB Connection</description> <res-ref-name>jdbc/testDB</res-ref-name> <res-type>javax.sql.DataSource</res-type> <res-auth>Container</res-auth> </resource-ref> </web-app> ``` the context.xml looks like this : ``` <?xml version="1.0" encoding="UTF-8"?> <Context path="/my1stApp" docBase="/var/www/jsp/my1stApp" debug="5" reloadable="true" crossContext="true"> <Resource name="jdbc/testDB" auth="Container" type="javax.sql.DataSource" maxActive="5" maxIdle="5" maxWait="10000" username="user" password="password" driverClassName="com.mysql.jdbc.Driver" url="jdbc:mysql://localhost:3306/some"/> </Context> ``` and the jsp file looks like this: ``` <%@ page contentType="text/html" %> <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %> <%@ taglib prefix="fn" uri="http://java.sun.com/jsp/jstl/functions" %> <%@ taglib prefix="fmt" uri="http://java.sun.com/jsp/jstl/fmt" %> <%@ taglib prefix="sql" uri="http://java.sun.com/jsp/jstl/sql" %> <html> <head> <title>DroneLootTool</title> </head> <body bgcolor="white"> <sql:query var="res" dataSource="jdbc/testDB"> select name, othername from mytable </sql:query> <h2>Results</h2> <c:forEach var="row" items="${res.rows}"> Name ${row.name}<br/> MoreName ${row.othername}<br/><br/> </c:forEach> </body> </html> ``` - read lots of forum entries / tried lots of different settings (always changed back to original settings when it didnt' work) - set TOMCAT6_SECURITY=no in /etc/default/tomcat6 because TOMCAT6_SECURITY=yes was causing trouble too - the skip-networking flag is not set for the DB (BIND 127.0.0.1 is set) - firewall is swiched off (sudo ufw disable) - MySQL works (tested several times with user used in this skript) telnet localhost 3306 says Trying ::1... Trying 127.0.0.1... Connected to localhost. Escape character is '^]'. Connection closed by foreign host. The TestConnection.java produced the following output: me@my-laptop:~/Desktop$ java -classpath '/usr/share/java/mysql.jar:./' TestConnection com.mysql.jdbc.Driver jdbc:mysql://localhost:3306/testDB myuser mypassword ``` com.mysql.jdbc.CommunicationsException: Communications link failure Last packet sent to the server was 0 ms ago. at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1070) at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2103) at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:718) at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:298) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:282) at java.sql.DriverManager.getConnection(DriverManager.java:582) at java.sql.DriverManager.getConnection(DriverManager.java:185) at TestConnection.checkConnection(TestConnection.java:40) at TestConnection.main(TestConnection.java:21) Caused by: com.mysql.jdbc.CommunicationsException: Communications link failure Last packet sent to the server was 0 ms ago. at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1070) at com.mysql.jdbc.MysqlIO.readPacket(MysqlIO.java:666) at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1069) at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2031) ... 7 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:2431) at com.mysql.jdbc.MysqlIO.readPacket(MysqlIO.java:590) ... 9 more Connection failed. ``` i don't know if there is a difference between the way the java driver connects to the DB and the Perl DBI module does, but this PERL skript works ``` #!/usr/bin/perl -w use CGI; use DBI; use strict; print CGI::header(); my $dbh = DBI->connect("dbi:mysql:some:localhost", "user", "password"); my $sSql = "SELECT * from mytable"; my $ppl = $dbh->selectall_arrayref( $sSql ); foreach my $pl (@$ppl) { my @array = @$pl; print @array; } $dbh->disconnect; ``` enabled --log-warnings on the mysql, but i didn't get any new warnings. When i was searching the logs for warnings i found this messages when i restart the tomcat, don't know if it helps to find the problem : ``` Feb 2 19:50:37 tobias-laptop jsvc.exec[3129]: 02.02.2010 19:50:37 org.apache.catalina.startup.HostConfig checkResources#012INFO: Undeploying context [/myapp] Feb 2 19:50:37 tobias-laptop jsvc.exec[3129]: 02.02.2010 19:50:37 org.apache.catalina.loader.WebappClassLoader clearReferencesThreads#012SCHWERWIEGEND: A web application appears to have started a thread named [MySQL Statement Cancellation Timer] but has failed to stop it. This is very likely to create a memory leak. Feb 2 19:50:37 tobias-laptop jsvc.exec[3129]: 02.02.2010 19:50:37 org.apache.catalina.startup.HostConfig deployDescriptor#012INFO: Deploying configuration descriptor myapp.xml ```