错误org.hibernate.util.JDBCExceptionReporter-通信链接失败

Question

我正在从事一个Spring ， MySQL和Hibernate项目，该项目还包含一个主应用程序，该应用程序在数据库中始终保持运行状态，但是根据几分钟的应用程序抛出异常

0    [Thread-1] ERROR org.hibernate.util.JDBCExceptionReporter  - Communications link failure

Last packet sent to the server was 1 ms ago.
Exception in thread "Thread-1" 3    [Thread-1] ERROR org.hibernate.util.JDBCExceptionReporter  - Communications link failure

Last packet sent to the server was 1 ms ago.
org.hibernate.exception.JDBCConnectionException: Cannot open connection
    at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:99)
    at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:66)
    at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:52)
    at org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:449)
    at org.hibernate.jdbc.ConnectionManager.getConnection(ConnectionManager.java:167)
    at org.hibernate.jdbc.AbstractBatcher.prepareQueryStatement(AbstractBatcher.java:161)
    at org.hibernate.loader.Loader.prepareQueryStatement(Loader.java:1596)
    at org.hibernate.loader.Loader.doQuery(Loader.java:717)
    at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:270)
    at org.hibernate.loader.Loader.doList(Loader.java:2294)
    at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2172)
    at org.hibernate.loader.Loader.list(Loader.java:2167)
    at org.hibernate.loader.criteria.CriteriaLoader.list(CriteriaLoader.java:119)
    at org.hibernate.impl.SessionImpl.list(SessionImpl.java:1706)
    at org.hibernate.impl.CriteriaImpl.list(CriteriaImpl.java:347)
    at com.qait.cdl.commons.dao.impl.CDLHibernateDaoImpl.findAll(CDLHibernateDaoImpl.java:77)
    at com.qait.cdl.insertIsbn.InsertIsbnDatabaseLookup.run(InsertIsbnDatabaseLookup.java:27)
    at java.lang.Thread.run(Thread.java:724)
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

Last packet sent to the server was 1 ms ago.
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:406)
    at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1074)
    at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2103)
    at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:718)
    at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:46)
    at sun.reflect.GeneratedConstructorAccessor11.newInstance(Unknown Source)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:406)
    at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:302)
    at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:282)
    at java.sql.DriverManager.getConnection(DriverManager.java:571)
    at java.sql.DriverManager.getConnection(DriverManager.java:187)
    at org.springframework.jdbc.datasource.DriverManagerDataSource.getConnectionFromDriverManager(DriverManagerDataSource.java:173)
    at org.springframework.jdbc.datasource.DriverManagerDataSource.getConnectionFromDriver(DriverManagerDataSource.java:164)
    at org.springframework.jdbc.datasource.AbstractDriverBasedDataSource.getConnectionFromDriver(AbstractDriverBasedDataSource.java:153)
    at org.springframework.jdbc.datasource.AbstractDriverBasedDataSource.getConnection(AbstractDriverBasedDataSource.java:119)
    at org.springframework.orm.hibernate3.LocalDataSourceConnectionProvider.getConnection(LocalDataSourceConnectionProvider.java:83)
    at org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:446)
    ... 14 more
Caused by: java.net.NoRouteToHostException: Cannot assign requested address
    at java.net.PlainSocketImpl.socketConnect(Native Method)
    at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:339)
    at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:200)
    at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:182)
    at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
    at java.net.Socket.connect(Socket.java:579)
    at java.net.Socket.connect(Socket.java:528)
    at java.net.Socket.<init>(Socket.java:425)
    at java.net.Socket.<init>(Socket.java:241)
    at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:253)
    at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:280)
    at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2026)
    ... 30 more

我搜索了许多链接，但没有确切/令人满意的原因以及如何克服

Answer 1

根本原因是NoRouteToHostException ，这意味着基础操作系统正在向JVM发送“主机没有路由” TCP / IP错误。 这表明数据库服务器与本机之间存在网络问题； 检查系统的操作系统日志（例如Linux上的dmesg ），以查看网卡是否存在连接故障。 如果不是这样，则说明您的网络路由存在间歇性问题，您需要与网络管理员进行故障排除。

Answer 2

就像我说的那样，有一个主应用程序在数据库中不断查找，在每次访问数据库时都会使用套接字，当所有套接字都被使用时，它将给出NoRouteToHostException ，该NoRouteToHostException由OS发送到JVM。 为了重用套接字，我在下面使用命令echo "1" >/proc/sys/net/ipv4/tcp_tw_reuse和/或echo "1" >/proc/sys/net/ipv4/tcp_tw_recycle ， 在此处进行解释。