linux重置mysql root密码的6种方法

#!/bin/bash
PATH=/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin:~/bin
export PATH

# Check if user is root
if [ $(id -u) != "0" ]; then
    printf "Error: You must be root to run this script!＼n"
    exit 1
fi

echo "=========================================================================＼n"
printf "Reset MySQL root Password for LNMP  ,  Written by Licess ＼n"
printf "=========================================================================＼n"
printf "LNMP is a tool to auto-compile & install Nginx+MySQL+PHP on Linux ＼n"
printf "This script is a tool to reset mysql root password for lnmp ＼n"
printf "For more information please visit http://www.111com.net ＼n"
printf "＼n"
printf "Usage: sh reset_mysql_root_password.sh＼n"
printf "=========================================================================＼n"

mysql_root_password=""
read -p "(Please input New MySQL root password):" mysql_root_password
if [ "$mysql_root_password" = "" ]; then
echo "Error: Password can't be NULL!!＼n"
exit 1
fi

printf "Stoping MySQL...＼n"
/etc/init.d/mysql stop
printf "Starting MySQL with skip grant tables＼n"
/usr/local/mysql/bin/mysqld_safe --skip-grant-tables >/dev/null 2>&1 &
printf "using mysql to flush privileges and reset password＼n"
sleep 10
printf "update user set password = Password('$mysql_root_password') where User = 'root'＼n"
/usr/local/mysql/bin/mysql -u root mysql << EOF
update user set password = Password('$mysql_root_password') where User = 'root';
EOF

reset_status=`echo $?`
if [ $reset_status = "0" ]; then
printf "Password reset succesfully. Now killing mysqld softly＼n"
killall mysqld
sleep 10
printf "Restarting the actual mysql service＼n"
/etc/init.d/mysql start
printf "Password successfully reset to '$mysql_root_password'＼n"
else
printf "Reset MySQL root password failed!＼n"
fi

#service mysqld stop

#mysqld_safe –skip-grant-tables & (我的mysqld_safe在/usr/bin，如果你的mysqld_safe不在PATH路径里面，那么这里要使用绝对路径)

这个时候root的密码为空,我们就可以免认证登录了

#mysql -u root

>

# ./mysql -u root
mysql> UPDATE mysql.user SET Password = PASSWORD('newpassword') WHERE User = 'root';
mysql> FLUSH PRIVILEGES;

1、停止MySQL进程

执行：/etc/init.d/mysql stop，具体位置可能随系统不同而不同，也可能是/etc/init.d/mysql，/etc/init.d/mysqld等路径，或下面直接终止（最好不要使用下面这个强制语句）：
 # killall -TERM mysqld
2、以安全模式启动MySQL
 

# mysqld_safe –skip-grant-tables &
或，
# mysqld_safe --skip-grant-tables >/dev/null 2>&1 &
提示：mysqld_safe一般在/usr/local/mysql/bin/目录下。
3、登陆MYSQL
完成上述两步以后就可以不用密码进入MySQL了
 
# mysql -u root
或，
# /usr/local/mysql/bin/mysql -u root mysql
4、更改ROOT密码
以下几句依次执行：
 

use mysql;
select host, user, password from user;
update user set password=password(“newpassword”) where user=”root”
flush privileges;

5.退出控制台，重启MYSQL服务

service mysqld restart
或，
/etc/init.d/mysql restart