I'm trying to connect to MySql (=MariaDB) on the localhost (lets call it A) from a tomcat webapp using Hibernate, but keep getting Communication link failure (the full exception trace attached below).
I have another replica of the DB on a different machine (lets call it B) and also using a 3rd computer for development (lets call it C).
1) I have no issues connecting from C to either of the DBs (A & B). 2) On "A" I have no problems connecting locally to the DB (running 'mysql -u' command). I also have no problems doing telnet on port 3306 to either A or B. so I assume both DBs are up and running and available for connections.
The only problem is when I'm trying to connect from the production tomcat (running on A) to either A or B db. I get the error:
com.mysql.cj.jdbc.exceptions.CommunicationsException: 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.
From similar cases of this error, I saw the majority of errors were due to invalid user/pass credentials or illegal IPs. I also tried to change the ip to localhost , 127.0.0.1 and 10.90.41.155 (which is the actual ip of the machine). Nothing helps, and also keep in mind that connection only fails from the specific tomcat installation on A.
I also tried the following: 1) Added "-Djava.net.preferIPv4Stack=true" to catalina startup 2) Tried to connect to illegal addresses/ports - this changed (as expected) the final error from "permission denied" into "no route to host". 3) Added the following to my connection string: "autoReconnect=true&useUnicode=true&createDatabaseIfNotExist=true&characterEncoding=utf-8" - this resulted in the same error ("Attempted reconnect 3 times. Giving up." + "Permission denied (connect failed)" 4) Tried both DB urls. for the local DB tried with localhost, 127.0.0.1 and the actual ip. tried both with and without ":3306" in the connection string
Attached is the hibernate.cfg file +full server trace of the exception:
<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-configuration SYSTEM
"http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<property name="hibernate.dialect">
org.hibernate.dialect.MySQLDialect
</property>
<property name="hibernate.connection.driver_class">
com.mysql.jdbc.Driver
</property>
<!-- Assume test is the database name -->
<property name="hibernate.connection.url">
jdbc:mysql://10.90.41.151/boonder
</property>
<property name="hibernate.connection.username">
root
</property>
<property name="hibernate.connection.password">
XXXXXXXXXX
</property>
<!-- List of XML mapping files -->
<mapping resource="User.hbm.xml"/>
<mapping resource="Issue.hbm.xml"/>
<mapping resource="TraderIssue.hbm.xml"/>
</session-factory>
</hibernate-configuration>
Exception is:
type Exception report
message Handler dispatch failed; nested exception is java.lang.ExceptionInInitializerError
description The server encountered an internal error that prevented it from fulfilling this request.
exception
org.springframework.web.util.NestedServletException: Handler dispatch failed; nested exception is java.lang.ExceptionInInitializerError
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:982)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)
org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872)
javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)
javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
com.aldondy.boonder.web.controllers.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:27)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
root cause
java.lang.ExceptionInInitializerError
com.aldondy.boonder.bl.DataSingleton.<init>(DataSingleton.java:54)
com.aldondy.boonder.bl.DataSingleton.instance(DataSingleton.java:74)
com.aldondy.boonder.web.controllers.LoginCtrl.loginInner(LoginCtrl.java:62)
com.aldondy.boonder.web.controllers.LoginCtrl.login(LoginCtrl.java:41)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
java.lang.reflect.Method.invoke(Method.java:498)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:180)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:440)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:428)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:967)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)
org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872)
javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)
javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
com.aldondy.boonder.web.controllers.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:27)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
root cause
org.hibernate.service.spi.ServiceException: Unable to create requested service [org.hibernate.engine.jdbc.env.spi.JdbcEnvironment]
org.hibernate.service.internal.AbstractServiceRegistryImpl.createService(AbstractServiceRegistryImpl.java:271)
org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:233)
org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:210)
org.hibernate.engine.jdbc.internal.JdbcServicesImpl.configure(JdbcServicesImpl.java:51)
org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:94)
org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:242)
org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:210)
org.hibernate.boot.model.process.spi.MetadataBuildingProcess.handleTypes(MetadataBuildingProcess.java:352)
org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:111)
org.hibernate.boot.model.process.spi.MetadataBuildingProcess.build(MetadataBuildingProcess.java:83)
org.hibernate.boot.internal.MetadataBuilderImpl.build(MetadataBuilderImpl.java:418)
org.hibernate.boot.internal.MetadataBuilderImpl.build(MetadataBuilderImpl.java:87)
org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:691)
org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:726)
com.aldondy.boonder.bl.DataSingleton.<init>(DataSingleton.java:48)
com.aldondy.boonder.bl.DataSingleton.instance(DataSingleton.java:74)
com.aldondy.boonder.web.controllers.LoginCtrl.loginInner(LoginCtrl.java:62)
com.aldondy.boonder.web.controllers.LoginCtrl.login(LoginCtrl.java:41)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
java.lang.reflect.Method.invoke(Method.java:498)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:180)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:440)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:428)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:967)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)
org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872)
javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)
javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
com.aldondy.boonder.web.controllers.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:27)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
root cause
org.hibernate.exception.JDBCConnectionException: Error calling Driver#connect
org.hibernate.exception.internal.SQLStateConversionDelegate.convert(SQLStateConversionDelegate.java:115)
org.hibernate.engine.jdbc.connections.internal.BasicConnectionCreator$1$1.convert(BasicConnectionCreator.java:101)
org.hibernate.engine.jdbc.connections.internal.BasicConnectionCreator.convertSqlException(BasicConnectionCreator.java:123)
org.hibernate.engine.jdbc.connections.internal.DriverConnectionCreator.makeConnection(DriverConnectionCreator.java:41)
org.hibernate.engine.jdbc.connections.internal.BasicConnectionCreator.createConnection(BasicConnectionCreator.java:58)
org.hibernate.engine.jdbc.connections.internal.PooledConnections.addConnections(PooledConnections.java:123)
org.hibernate.engine.jdbc.connections.internal.PooledConnections.<init>(PooledConnections.java:42)
org.hibernate.engine.jdbc.connections.internal.PooledConnections.<init>(PooledConnections.java:20)
org.hibernate.engine.jdbc.connections.internal.PooledConnections$Builder.build(PooledConnections.java:161)
...
org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:691)
org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:726)
com.aldondy.boonder.bl.DataSingleton.<init>(DataSingleton.java:48)
com.aldondy.boonder.bl.DataSingleton.instance(DataSingleton.java:74)
com.aldondy.boonder.web.controllers.LoginCtrl.loginInner(LoginCtrl.java:62)
com.aldondy.boonder.web.controllers.LoginCtrl.login(LoginCtrl.java:41)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
java.lang.reflect.Method.invoke(Method.java:498)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:180)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:440)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:428)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:967)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)
org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872)
javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)
javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
com.aldondy.boonder.web.controllers.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:27)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
root cause
com.mysql.cj.jdbc.exceptions.CommunicationsException: 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.
com.mysql.cj.jdbc.exceptions.SQLError.createCommunicationsException(SQLError.java:166)
com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:58)
com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:853)
com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:440)
com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:241)
com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:221)
org.hibernate.engine.jdbc.connections.internal.DriverConnectionCreator.makeConnection(DriverConnectionCreator.java:38)
org.hibernate.engine.jdbc.connections.internal.BasicConnectionCreator.createConnection(BasicConnectionCreator.java:58)
...
org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:210)
org.hibernate.boot.model.process.spi.MetadataBuildingProcess.handleTypes(MetadataBuildingProcess.java:352)
org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:111)
org.hibernate.boot.model.process.spi.MetadataBuildingProcess.build(MetadataBuildingProcess.java:83)
org.hibernate.boot.internal.MetadataBuilderImpl.build(MetadataBuilderImpl.java:418)
org.hibernate.boot.internal.MetadataBuilderImpl.build(MetadataBuilderImpl.java:87)
org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:691)
org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:726)
com.aldondy.boonder.bl.DataSingleton.<init>(DataSingleton.java:48)
com.aldondy.boonder.bl.DataSingleton.instance(DataSingleton.java:74)
com.aldondy.boonder.web.controllers.LoginCtrl.loginInner(LoginCtrl.java:62)
com.aldondy.boonder.web.controllers.LoginCtrl.login(LoginCtrl.java:41)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
java.lang.reflect.Method.invoke(Method.java:498)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:180)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:440)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:428)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:967)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)
org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872)
javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)
javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
com.aldondy.boonder.web.controllers.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:27)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
root cause
com.mysql.cj.core.exceptions.CJCommunicationsException: 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.
sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
java.lang.reflect.Constructor.newInstance(Constructor.java:423)
com.mysql.cj.core.exceptions.ExceptionFactory.createException(ExceptionFactory.java:54)
com.mysql.cj.core.exceptions.ExceptionFactory.createException(ExceptionFactory.java:93)
com.mysql.cj.core.exceptions.ExceptionFactory.createException(ExceptionFactory.java:133)
com.mysql.cj.core.exceptions.ExceptionFactory.createCommunicationsException(ExceptionFactory.java:149)
com.mysql.cj.mysqla.io.MysqlaSocketConnection.connect(MysqlaSocketConnection.java:83)
com.mysql.cj.mysqla.MysqlaSession.connect(MysqlaSession.java:204)
com.mysql.cj.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:975)
com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:843)
com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:440)
com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:241)
com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:221)
org.hibernate.engine.jdbc.connections.internal.DriverConnectionCreator.makeConnection(DriverConnectionCreator.java:38)
org.hibernate.engine.jdbc.connections.internal.BasicConnectionCreator.createConnection(BasicConnectionCreator.java:58)
org.hibernate.engine.jdbc.connections.internal.PooledConnections.addConnections(PooledConnections.java:123)
org.hibernate.engine.jdbc.connections.internal.PooledConnections.<init>(PooledConnections.java:42)
org.hibernate.engine.jdbc.connections.internal.PooledConnections.<init>(PooledConnections.java:20)
org.hibernate.engine.jdbc.connections.internal.PooledConnections$Builder.build(PooledConnections.java:161)
org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl.buildPool(DriverManagerConnectionProviderImpl.java:109)
org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl.configure(DriverManagerConnectionProviderImpl.java:72)
org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:94)
org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:242)
org.hibernate.engine.jdbc.internal.JdbcServicesImpl.configure(JdbcServicesImpl.java:51)
org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:94)
org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:242)
org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:210)
org.hibernate.boot.model.process.spi.MetadataBuildingProcess.handleTypes(MetadataBuildingProcess.java:352)
org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:111)
org.hibernate.boot.model.process.spi.MetadataBuildingProcess.build(MetadataBuildingProcess.java:83)
org.hibernate.boot.internal.MetadataBuilderImpl.build(MetadataBuilderImpl.java:418)
org.hibernate.boot.internal.MetadataBuilderImpl.build(MetadataBuilderImpl.java:87)
org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:691)
org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:726)
com.aldondy.boonder.bl.DataSingleton.<init>(DataSingleton.java:48)
com.aldondy.boonder.bl.DataSingleton.instance(DataSingleton.java:74)
com.aldondy.boonder.web.controllers.LoginCtrl.loginInner(LoginCtrl.java:62)
com.aldondy.boonder.web.controllers.LoginCtrl.login(LoginCtrl.java:41)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
java.lang.reflect.Method.invoke(Method.java:498)
org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:180)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:440)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:428)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:967)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)
org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872)
javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)
javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
com.aldondy.boonder.web.controllers.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:27)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
root cause
java.net.SocketException: Permission denied (connect failed)
java.net.PlainSocketImpl.socketConnect(Native Method)
java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350)
java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)
java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188)
java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
java.net.Socket.connect(Socket.java:589)
com.mysql.cj.core.io.StandardSocketFactory.connect(StandardSocketFactory.java:202)
com.mysql.cj.mysqla.io.MysqlaSocketConnection.connect(MysqlaSocketConnection.java:57)
com.mysql.cj.mysqla.MysqlaSession.connect(MysqlaSession.java:204)
com.mysql.cj.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:975)
com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:843)
com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:440)
com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:241)
com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:221)
org.hibernate.engine.jdbc.connections.internal.DriverConnectionCreator.makeConnection(DriverConnectionCreator.java:38)
org.hibernate.engine.jdbc.connections.internal.BasicConnectionCreator.createConnection(BasicConnectionCreator.java:58)
org.hibernate.engine.jdbc.connections.internal.PooledConnections.addConnections(PooledConnections.java:123)
org.hibernate.engine.jdbc.connections.internal.PooledConnections.<init>(PooledConnections.java:42)
org.hibernate.engine.jdbc.connections.internal.PooledConnections.<init>(PooledConnections.java:20)
org.hibernate.engine.jdbc.connections.internal.PooledConnections$Builder.build(PooledConnections.java:161)
org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl.buildPool(DriverManagerConnectionProviderImpl.java:109)
org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl.configure(DriverManagerConnectionProviderImpl.java:72)
org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:94)
org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:242)
org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:210)
org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.buildJdbcConnectionAccess(JdbcEnvironmentInitiator.java:145)
org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.initiateService(JdbcEnvironmentInitiator.java:66)
org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.initiateService(JdbcEnvironmentInitiator.java:35)
org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.initiateService(StandardServiceRegistryImpl.java:88)
org.hibernate.service.internal.AbstractServiceRegistryImpl.createService(AbstractServiceRegistryImpl.java:259)
org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:233)
org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:210)
...
org.hibernate.boot.internal.MetadataBuilderImpl.build(MetadataBuilderImpl.java:87)
org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:691)
org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:726)
com.aldondy.boonder.bl.DataSingleton.<init>(DataSingleton.java:48)
com.aldondy.boonder.bl.DataSingleton.instance(DataSingleton.java:74)
com.aldondy.boonder.web.controllers.LoginCtrl.loginInner(LoginCtrl.java:62)
com.aldondy.boonder.web.controllers.LoginCtrl.login(LoginCtrl.java:41)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
java.lang.reflect.Method.invoke(Method.java:498)
org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:428)
org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:967)
org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901)
org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)
org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872)
javax.servlet.http.HttpServlet.service(HttpServlet.java:650)
org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)
javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
com.aldondy.boonder.web.controllers.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:27)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
note The full stack trace of the root cause is available in the Apache Tomcat/7.0.76 logs.
I just also tracked down this issue. My symptoms were the exact same as yours and I even tried the exact things you tried. In summary my problem only occured because I was using tomcat on centos with SELinux.
Some folks helped me diagnose using the following commands to look at security events and why some actions were not permittted:
sudo ausearch -m avc
sudo grep "tcp_socket" /var/log/audit/audit.log | audit2why // translates log into some human readable reasons why the audit record was generated
I saw entries like:
type=AVC msg=audit(1507861264.561:64750): avc: denied { name_connect } for pid=1326 comm="java" dest=3306 scontext=system_u:system_r:tomcat_t:s0 tcontext=system_u:object_r:mysqld_port_t:s0 tclass=tcp_socket
Was caused by: Missing type enforcement (TE) allow rule.
You can use audit2allow to generate a loadable module to allow this access.
And then found this article about tomcat and SELinux https://noobient.com/post/165972214381/selinux-woes-with-tomcat-on-centos-74
You can run the following command to see if tomcat is running in the tomcat_t security context.
$ps auxZ | grep tomcat
For the purposes of truly determining if my error was SELinux, I disabled SELinux
$ sestatus // shows: SELinux status: enabled
$ sudo vim /etc/selinux/config // set "SELINUX=disabled"
$ sudo shutdown -r now
$ sestatus // shows: SELinux status: disabled
restarted my machine and saw that tomcat was now making the outbound connection.
Great, now I at least know WHY that was happening. Of course if you need SELinux, disabling it is NOT a solution. Another workaround which is probably not a solution is to install tomcat without going through yum. Yum will installed tomcat using the security context.
I think the course of action now is to modify the security context or set of rules governing tomcat to allow it to make outgoing connections.
来源：https://stackoverflow.com/questions/46689530/tomcat-hibernate-connection-to-mysql-fails-with-communications-link-failure