问题现象 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. I spend some days to solve this…

使用Connector/J连接MySQL数据库,程序运行较长时间后就会报以下错误: Communications link failure,The last packet successfully received from the server was *** millisecond ago.The last packet successfully sent to the server was *** millisecond ago. 其中错误还会提示你修改wait_timeout或是使用Co…

想必大家在用MySQL时都会遇到连接超时的问题,如下图所示: 就是这个异常(com.mysql.jdbc.exceptions.jdbc4.Communication***ception:Communications link failure Last packet sent to the server was X ms ago),是由于MySQL服务在长时间不连接之后断开了,断开之后的首次请求会抛出这个异常.那么既然是连接超时的问题,就要去MySQL中探究一下连接时间是怎么控制的.打开MySQ…

MySQL默认一个连接空闲8小时候就会自动断开,而这时程序以为连接还能使用,然后在使用的时候就会出现Communications link failure异常. 这时需要进行两步设置,有时候只设置MySQL就可以了. 一.在MySQL的配置文件(linux配置文件是my.cnf,windows配置文件为my.ini)中添加以下两行(默认值为28800,下面的值代表一年.听说windows下的MySQL不支持一年,可以适当减少尝试) wait_timeout=31536000 interactiv…

一.背景 最近在家里捣鼓一个公司自己搭建的demo的时候,发现程序一启动就会出现CommunicationsException: Communications link failure错误,经过一番排查最后发现是数据库url写错造成的,这个过程中也对出现这个错误的解决思路有了一些自己的理解,现和大家分享.该错误的具体信息如下: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure…

09:00:30.307 [http-8080-6] ERROR org.hibernate.transaction.JDBCTransaction -JDBC begin failed com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure The last packet successfully received from the server was 56,237,340 mi…

最近在用一个MySQL的Java连接池的过程中,连接一晚上不释放,第二天就会造成超时的错误,查了一下原因,原来是因为MySQL默认的空闲等待时间是8个小时,一旦空闲超过8个小时,就会抛出异常.异常文本如下: com.mysql.jdbc.CommunicationsException MESSAGE: Communications link failure due to underlying exception: ** BEGIN NESTED EXCEPTION ** java.net.Soc…

异常描述 这个异常通常有如下信息: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure The last packet successfully received from the server was 59,977 milliseconds ago. The last packet sent successfully to the server was 1 millisecon…

在使用JDBC连接mysql时可能会遇到以下错误: 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 解决方法: 将 Str…

报错: MySQL第二天早上第一次连接超时报错, com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure 原因: 上述问题是由mysql5数据库的配置引起的.mysql5将其连接的等待时间(wait_timeout .interactive_timeout)缺省为8小时.在其客户程序中可以这样来查看其值: mysql> show global variables like 'wait…