Linux下mysql第一次登陆跳过密码

mysql在第一次登陆时会提示ERROR 1045 (28000): Access denied for user root@localhost。

现在网上流传的使用mysqladmin或者mysqld_safe命令来启动已经不行了。新版本的mysql已经移除了mysqld_safe， mysqladmin还在，但是仍然无法登陆。

亲测有用的另一种方法：

Step 1 编辑/etc/my.cnf

root@linux: vim /etc/my.cnf

在mysqld项最末尾加上一行 skip-grant-tables

[mysqld]
#
# 省略若干行
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0

log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid
skip-grant-tables

Step 2 重启mysql服务，修改root用户密码

root@linux: service mysqld restart
root@linux: mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 3
Server version: 5.7.18 MySQL Community Server (GPL)

Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql> update mysql.user set authentication_string=password('newpasswd') where user='root';
mysql> exit;

Step 3 恢复设置, 再次重启mysql服务

删除/etc/my.cnf 最后的skip-grant-tables, 并重启mysql服务。

root@linux: vim /etc/my.cnf
[mysqld]
#
# 省略若干行
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0

log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid

root@linux: service mysqld restart

大功告成！