zoukankan      html  css  js  c++  java
  • MySQL ERROR Got an error reading communication packets

    介绍

    经常会在错误日志中看到这个报错,首先我们可以从show GLOBAL status like '%Aborte%';里面看看两种错误连接的数量,以下是复制官方文档的解释。   

    Aborted_connects 

    If a client is unable even to connect, the server increments the Aborted_connects status variable. Unsuccessful connection attempts can occur for the following reasons:

    If these kinds of things happen, it might indicate that someone is trying to break into your server! If the general query log is enabled, messages for these types of problems are logged to it.

    对于Aborted_connects错误的大概原因有:

    1.客户端连接一个没有授权的数据库

    2.密码错误

    3.连接包信息错误

    4.连接超时(默认10s)

    Aborted_clients

    If a client successfully connects but later disconnects improperly or is terminated, the server increments the Aborted_clients status variable, and logs an Aborted connection message to the error log. The cause can be any of the following:

    Other reasons for problems with aborted connections or aborted clients:

    • The max_allowed_packet variable value is too small or queries require more memory than you have allocated for mysqld. See Section B.5.2.10, “Packet Too Large”.

    • Use of Ethernet protocol with Linux, both half and full duplex. Some Linux Ethernet drivers have this bug. You should test for this bug by transferring a huge file using FTP between the client and server machines. If a transfer goes in burst-pause-burst-pause mode, you are experiencing a Linux duplex syndrome. Switch the duplex mode for both your network card and hub/switch to either full duplex or to half duplex and test the results to determine the best setting.

    • A problem with the thread library that causes interrupts on reads.

    • Badly configured TCP/IP.

    • Faulty Ethernets, hubs, switches, cables, and so forth. This can be diagnosed properly only by replacing hardware.

    对于 Aborted_clients的原因大概有

    1.客户端没有执行mysql_close()关闭

    2.由于连接一直没有关闭导致时间超过wait_timeout or interactive_timeout这两个变量的值(这两个变量的超时时间是8小时)

    3.客户端在程序执行过程中结束

    4.max_allowed_packet包设的过小

    5.网络原因

    6.线程bug等

    总结

     

    备注:

        作者:pursuer.chen

        博客:http://www.cnblogs.com/chenmh

    本站点所有随笔都是原创,欢迎大家转载;但转载时必须注明文章来源,且在文章开头明显处给明链接。

    《欢迎交流讨论》

  • 相关阅读:
    ibatis 循环迭代
    javascript 中Table、TableCell 、TableRow对象
    Java重载Java构造器
    java垃圾回收机制
    Java在J2EE工程中路径寻址问题终极解决方案
    JAVASCRIPT 验证计算中英文混合字符串长度的解决
    java基础学习及总结
    ORACLE nvarchar2和varchar2的区别
    StringBuffer的用法
    关于Ant下的路径查找
  • 原文地址:https://www.cnblogs.com/chenmh/p/5852490.html
Copyright © 2011-2022 走看看