• 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:
    Linux随笔 DNS搭建
    总算亲自看见了一个网站被黑后的页面。
    [转]XP如何禁止媒体文件预览
    用Word2007发Blog的配置方法(多图)。
    C#通过http访问olap
    测试Word2007
    用IronPython作为.Net的脚本语言。
    用批处理写的显示磁盘剩余空间的小程序。
    事开机时Num Lock键打开。
    快捷方便的对js文件进行语法检查。
  • 原文地址:https://www.cnblogs.com/chenmh/p/5852490.html
Copyright © 2020-2023  润新知