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Linux卸载yum安装的mysql

一、系统情况

Linux：Centos7.4（64位）

Mysql：5.6

二、卸载mysql

1.查看安装了哪些mysql程序

Bash

rpm -qa | grep -i mysql # 命令1 yum list install mysql* # 或命令2

2.使用yum remove卸载

Bash

yum remove mysql mysql-server mysql-libs compat-mysql51
yum remove mysql-community-release

3.剩下卸载不了使用

Bash

rpm -e --nodeps mysql-community-libs-5.7.22-1.el7.x86_64
rpm -e –nodeps mysql57-community-release-el7-11.noarch

4.删除残留的mysql的目录或文件

Bash

whereis mysql 或 find / -name mysql #注意不要误删其他程序的mysql文件夹 rm -rf /usr/lib64/mysql rm -rf /usr/share/mysql rm -rf /usr/bin/mysql rm -rf /etc/logrotate.d/mysql rm -rf /var/lib/mysql rm -rf /var/lib/mysql/mysql

5.删除mysql配置文件

Bash

rm –rf /usr/my.cnf rm -rf /root/.mysql_sercret

6.删除mysql开机自启动服务

Bash

chkconfig --list | grep -i mysql #查看mysql的服务 chkconfig --del mysqld #服务名为你设置时候自己设置的名字

Linux yum安装MySQL5.7

 一、安装配置MySQL的yum源

1 2 3 4 5 6 7 8 9 10

# 安装MySQL的yum源，下面是RHEL6系列的下载地址 rpm -Uvh http: //dev .mysql.com /get/mysql-community-release-el6-5 .noarch.rpm # 安装yum-config-manager yum  install  yum-utils -y # 禁用MySQL5.6的源 yum-config-manager --disable mysql56-community # 启用MySQL5.7的源 yum-config-manager -- enable  mysql57-community-dmr # 用下面的命令查看是否配置正确 yum repolist enabled |  grep  mysql

    检查是否有mysql57-community-dmr这个源，如上图所示。

    二、yum安装MySQL5.7

1 2	# 安装MySQL5.7 yum  install  mysql-community-server

    三、启动MySQL

1 2 3 4 5

# 禁用selinux setenforce 0 sed  -i  '/^SELINUX=/c\SELINUX=disabled'  /etc/selinux/config  # 启动mysqld，启动之前先修改/etc/my.cnf配置文件，本文用默认的配置。 service mysqld start

    四、连接MySQL并修改密码

 

MySQL忘记密码，或：root密码重置报错：mysqladmin: connect to server at 'localhost' failed的解决方案

MySQL root密码重置报错： mysqladmin: connect to server at 'localhost' failed的解决方案

 

1  登陆失败,mysqladmin修改密码失败

[root@mysql var]# mysqladmin -u root password '123456'

mysqladmin: connect to server at 'localhost' failed

error: 'Access denied for user 'root'@'localhost' (using password: NO)'

 

2 停止mysql服务

[root@mysql var]# /etc/init.d/mysqld stop

Shutting down MySQL.... SUCCESS!

 

3 安全模式启动

[root@mysql var]# mysqld_safe --skip-grant-tables &

（路径不一样：/opt/mysql/product/5.5.25a/bin/mysqld_safe --skip-grant-tables &）

[1] 10912

[root@mysql var]# 110407 17:39:28 mysqld_safe Logging to '/usr/local/mysql/var//mysql.chinascopefinanical.com.err'.

110407 17:39:29 mysqld_safe Starting mysqld daemon with databases from /usr/local/mysql/var/

 

4 无密码root帐号登陆

[root@mysql var]# /usr/bin/mysql -u root -p 【注释，在下面的要求你输入密码的时候，你不用管，直接回车键一敲就过去了】

Enter password:

Welcome to the MySQL monitor.  Commands end with ; or \g.

Your MySQL connection id is 48

Server version: 5.1.41-log Source distribution

 

 

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

 

 

mysql> use mysql;

Database changed

 

5 手动update修改密码

mysql> update mysql.user set authentication_string=password("123456") where user='root' and host='localhost';

Query OK, 1 row affected (0.00 sec)

Rows matched: 1  Changed: 1  Warnings: 0

 

 

mysql> flush privileges;

Query OK, 0 rows affected (0.00 sec)

 

 

mysql> quit

Bye

[root@mysql var]# mysql -u root -p guNNhtqhjUnfky6ahyVh

Welcome to the MySQL monitor.  Commands end with ; or \g.

Your MySQL connection id is 172

Server version: 5.1.41-log Source distribution

 

 

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

 

 

mysql> quit

Bye

 

 

6 正常重新启动

[root@mysql var]# service mysqld restart

Shutting down MySQL..110407 17:45:29 mysqld_safe mysqld from pid file /usr/local/mysql/var//mysql.chinascopefinanical.com.pid ended

SUCCESS!

Starting MySQL.. SUCCESS!