记录linux 安装 MYSQL 的点点滴滴

 1：今天当我mysql 的时候，报错： 

[root@oc2246430752 etc]# mysql

ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2)

后来，当我安装好：

yum install -y mariadb-server

提示：Package mariadb-server is obsoleted by mysql-community-server, trying to install mysql-community-server-5.7.25-1.el7.x86_64 instead

下面开始安装：mysql-community-server-5.7.25-1.el7.x86_64.rpm

2： 安装后还是同样报错：

[root@oc2246430752 etc]# mysql

ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2)

3：看了我是mqsql 没有启动:

启动后报另外一个错：

[root@oc2246430752 init.d]# service mysqld start

Redirecting to /bin/systemctl start mysqld.service

[root@oc2246430752 init.d]# mysql

ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO)

4：原来是密码问题，

用grep 'temporary password' /var/log/mysqld.log 把密码显示出来；

mysql -uroot -p 输入默认的密码，然后修改

mysql> set password=password( "Sheng2020");  （注意是双引号）

Query OK, 0 rows affected, 1 warning (0.00 sec)

mysql> select @@validate_password_length;

+----------------------------+

| @@validate_password_length |

+----------------------------+

| 8 |

+----------------------------+

1 row in set (0.00 sec)

mysql> SHOW VARIABLES LIKE 'validate_password%';

+--------------------------------------+-------+

| Variable_name | Value |

+--------------------------------------+-------+

| validate_password_check_user_name | OFF |

| validate_password_dictionary_file | |

| validate_password_length | 8 |

| validate_password_mixed_case_count | 1 |

| validate_password_number_count | 1 |

| validate_password_policy | LOW |

| validate_password_special_char_count | 1 |

+--------------------------------------+-------+

7 rows in set (0.01 sec)

mysql>

下面连接数据库：[root@oc2246430752 log]# mysql

ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO)

[root@oc2246430752 ~]# mysql -h127.0.0.1 -uroot -pSheng2020 -P3306

mysql: [Warning] Using a password on the command line interface can be insecure.

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

Your MySQL connection id is 5

Server version: 5.7.25 MySQL Community Server (GPL)

Copyright (c) 2000, 2019, 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>

成功了。