服务器环境：CentOS6.2 + Nginx1.4.4 + Mysql 5.1.60 +Tomcat 7.0.14 顺利安装jeecms 5.1（安装包版），但运行后，不论前台还是后台，都会偶尔出来以下500错误信息。出现该信息号，刷新该页面，又可正常访问。但不定期的还是会出现500。网上查资料貌似是JDBC驱动设置要有个持久性什么的，请问版主，这个该在哪里修改配置文件呢？ HTTP Status 500 - Request processing failed; nested exception is org.springframework.transaction.CannotCreateTransactionException: Could not open Hibernate Session for transaction; nested exception is org.hibernate.TransactionException: JDBC begin failed: type Exception report message Request processing failed; nested exception is org.springframework.transaction.CannotCreateTransactionException: Could not open Hibernate Session for transaction; nested exception is org.hibernate.TransactionException: JDBC begin failed: description The server encountered an internal error that prevented it from fulfilling this request. exception org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.springframework.transaction.CannotCreateTransactionException: Could not open Hibernate Session for transaction; nested exception is org.hibernate.TransactionException: JDBC begin failed:  org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:656) org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:549) javax.servlet.http.HttpServlet.service(HttpServlet.java:621) javax.servlet.http.HttpServlet.service(HttpServlet.java:728) org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:198) org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76) org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88) org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76) com.jeecms.common.web.ProcessTimeFilter.doFilter(ProcessTimeFilter.java:35) root cause org.springframework.transaction.CannotCreateTransactionException: Could not open Hibernate Session for transaction; nested exception is org.hibernate.TransactionException: JDBC begin failed:  org.springframework.orm.hibernate3.HibernateTransactionManager.doBegin(HibernateTransactionManager.java:596) org.springframework.transaction.support.AbstractPlatformTransactionManager.getTransaction(AbstractPlatformTransactionManager.java:371) org.springframework.transaction.interceptor.TransactionAspectSupport.createTransactionIfNecessary(TransactionAspectSupport.java:335) org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:105) org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172) org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202) com.sun.proxy.$Proxy57.retrieveUserIdFromSession(Unknown Source) com.jeecms.cms.web.FrontContextInterceptor.preHandle(FrontContextInterceptor.java:80) org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:781) org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:719) org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:644) org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:549) javax.servlet.http.HttpServlet.service(HttpServlet.java:621) javax.servlet.http.HttpServlet.service(HttpServlet.java:728) org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:198) org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76) org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88) org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76) com.jeecms.common.web.ProcessTimeFilter.doFilter(ProcessTimeFilter.java:35) root cause org.hibernate.TransactionException: JDBC begin failed:  org.hibernate.transaction.JDBCTransaction.begin(JDBCTransaction.java:96) org.hibernate.impl.SessionImpl.beginTransaction(SessionImpl.java:1354) org.springframework.orm.hibernate3.HibernateTransactionManager.doBegin(HibernateTransactionManager.java:555) org.springframework.transaction.support.AbstractPlatformTransactionManager.getTransaction(AbstractPlatformTransactionManager.java:371) org.springframework.transaction.interceptor.TransactionAspectSupport.createTransactionIfNecessary(TransactionAspectSupport.java:335) org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:105) org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172) org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202) com.sun.proxy.$Proxy57.retrieveUserIdFromSession(Unknown Source) com.jeecms.cms.web.FrontContextInterceptor.preHandle(FrontContextInterceptor.java:80) org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:781) org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:719) org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:644) org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:549) javax.servlet.http.HttpServlet.service(HttpServlet.java:621) javax.servlet.http.HttpServlet.service(HttpServlet.java:728) org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:198) org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76) org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88) org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76) com.jeecms.common.web.ProcessTimeFilter.doFilter(ProcessTimeFilter.java:35) root cause com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure The last packet successfully received from the server was 300,372 milliseconds ago.  The last packet sent successfully to the server was 1 milliseconds ago. sun.reflect.GeneratedConstructorAccessor71.newInstance(Unknown Source) sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27) java.lang.reflect.Constructor.newInstance(Constructor.java:513) com.mysql.jdbc.Util.handleNewInstance(Util.java:406) com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1074) com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3030) com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2916) com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3459) com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1957) com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2107) com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2642) com.mysql.jdbc.ConnectionImpl.setAutoCommit(ConnectionImpl.java:5036) com.mchange.v2.c3p0.impl.NewProxyConnection.setAutoCommit(NewProxyConnection.java:881) org.hibernate.transaction.JDBCTransaction.begin(JDBCTransaction.java:91) org.hibernate.impl.SessionImpl.beginTransaction(SessionImpl.java:1354) org.springframework.orm.hibernate3.HibernateTransactionManager.doBegin(HibernateTransactionManager.java:555) org.springframework.transaction.support.AbstractPlatformTransactionManager.getTransaction(AbstractPlatformTransactionManager.java:371) org.springframework.transaction.interceptor.TransactionAspectSupport.createTransactionIfNecessary(TransactionAspectSupport.java:335) org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:105) org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172) org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202) com.sun.proxy.$Proxy57.retrieveUserIdFromSession(Unknown Source) com.jeecms.cms.web.FrontContextInterceptor.preHandle(FrontContextInterceptor.java:80) org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:781) org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:719) org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:644) org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:549) javax.servlet.http.HttpServlet.service(HttpServlet.java:621) javax.servlet.http.HttpServlet.service(HttpServlet.java:728) org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:198) org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76) org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88) org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76) com.jeecms.common.web.ProcessTimeFilter.doFilter(ProcessTimeFilter.java:35) root cause java.io.EOFException: Can not read response from server. Expected to read 4 bytes, read 0 bytes before connection was unexpectedly lost. com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:2475) com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2927) com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2916) com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3459) com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1957) com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2107) com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2642) com.mysql.jdbc.ConnectionImpl.setAutoCommit(ConnectionImpl.java:5036) com.mchange.v2.c3p0.impl.NewProxyConnection.setAutoCommit(NewProxyConnection.java:881) org.hibernate.transaction.JDBCTransaction.begin(JDBCTransaction.java:91) org.hibernate.impl.SessionImpl.beginTransaction(SessionImpl.java:1354) org.springframework.orm.hibernate3.HibernateTransactionManager.doBegin(HibernateTransactionManager.java:555) org.springframework.transaction.support.AbstractPlatformTransactionManager.getTransaction(AbstractPlatformTransactionManager.java:371) org.springframework.transaction.interceptor.TransactionAspectSupport.createTransactionIfNecessary(TransactionAspectSupport.java:335) org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:105) org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172) org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202) com.sun.proxy.$Proxy57.retrieveUserIdFromSession(Unknown Source) com.jeecms.cms.web.FrontContextInterceptor.preHandle(FrontContextInterceptor.java:80) org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:781) org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:719) org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:644) org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:549) javax.servlet.http.HttpServlet.service(HttpServlet.java:621) javax.servlet.http.HttpServlet.service(HttpServlet.java:728) org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:198) org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76) org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88) org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76) com.jeecms.common.web.ProcessTimeFilter.doFilter(ProcessTimeFilter.java:35) note The full stack trace of the root cause is available in the Apache Tomcat/7.0.47 logs. Apache Tomcat/7.0.47

java.io.EOFException: Can not read response from server. Expected to read 4 bytes, read 0 bytes before connection was unexpectedly lost. 
com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:2475) 
com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2927) 
com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:2916) 

连接池设置 
  <Resource 
  name= "jdbc/song " 
  type= "javax.sql.DataSource " 
  driverClassName= "com.mysql.jdbc.Driver " 
  password= "haishui " 
  maxIdle= "20 " 　　　你改下你连接池设置

原因大致为：当修改系统日期后Mysql自动关闭已打开的连接，可以数据库连接池(DBCP)还认为这些连接是活动的，如果这时有请求（需要执行读写数据库的操作），连接池就用一个连接去操作数据库，而这个连接在Mysql的连接池中并不存在，所以会出现以上的异常。如果一个连接在和Mysql建立连接时能检查就不会有这样的问题了。 

一个数据库连接池proxool，它有两个属性：一个是test-before-use，还有一个是test-after-use，这两个属性就是在使用前和使用后都要进行对连接的检查，如果连接无效就扔掉再创建一个新的连接，它们的解释如下： 

test-before-use: 

If you set this to true then each connection is tested (with whatever is defined in house-keeping-test-sql) before being served. If a connection fails then it is discarded and another one is picked. If all connections fail a new one is built. If that one fails then you get an SQLException saying so. 

test-after-use: 

If you set this to true then each connection is tested (with whatever is defined in house-keeping-test-sql) after it is closed (that is, returned to the connection pool). If a connection fails then it is discarded. 

于是我们在项目中换上proxool的连接池，再运行并访问系统，更改系统时间，再访问，不但如此，proxool的连接池中的连接的数量，活动数以及每个连接的的具体情况都可以一目了然的看到

回复第3楼

请问改哪个文件呢。具体位置是？

改你数据库连接池，这和jeecms没有关联，是你数据连接池的问题

数据连接池一般在哪里改啊，我不懂jsp哦。

这需要你研究数据库方面的知识了，你用的mysql数据库版本比较低的吧？你也可以换个mysql*的没你这问题

是tomcat7的server.xml的<Resource name="UserDatabase" auth="Container"
              type="org.apache.catalina.UserDatabase"
              description="User database that can be updated and saved"
              factory="org.apache.catalina.users.MemoryUserDatabaseFactory"
              pathname="conf/tomcat-users.xml" />
吗？

是的