Question

我有以下情况：

我可以

通过命令行工具mysql连接到我的mysql数据库，来自本地计算机和远程主机
从远程主机

我不能

从本地计算机

测试代码与this question中的测试代码基本相同，我遵循了那里给出的所有建议，无法解决我的问题。我尝试了以下连接字符串：

JDBC：MySQL的：//本地主机/数据库
JDBC：MySQL的：//本地主机：3306 /数据库
JDBC：MySQL的：//127.0.0.1/database
JDBC：MySQL的：//主机名/数据库

所有导致相同的错误消息。在远程机器上，我可以毫无问题地使用第四种替代方案。

我正在运行mysql-5.5服务器。远程使用java版本“1.7.0_101”，本地机器使用java版本“1.6.0_38”。

以下是在本地计算机上运行java程序时的错误消息：

Connecting to database...
com.mysql.jdbc.exceptions.jdbc4.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.
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:534)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1116)
at com.mysql.jdbc.MysqlIO.readPacket(MysqlIO.java:688)
at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1094)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2337)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2370)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2154)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:792)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)
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:534)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:381)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:305)
at java.sql.DriverManager.getConnection(DriverManager.java:615)
at java.sql.DriverManager.getConnection(DriverManager.java:195)
at FirstExample.main(FirstExample.java:22)
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:2540)
at com.mysql.jdbc.MysqlIO.readPacket(MysqlIO.java:612)
... 16 more
Goodbye!

Answer 1

我刚刚意识到mysql -u user database可行，但不是mysql -u user -h 127.0.0.1 database，所以事实证明我的/etc/hosts.allow文件中有错误。问题解决了！

远程连接工作时无法从本地连接到mysql的mysql

1 个答案: