用户的密码管理
给用户改密码
- 初始化mysql后设置初始密码
mysqladmin -uroot password 'wzy666'
- 改变已有密码
mysqladmin -uroot -pwzy666 password 'wzy999'
- SQL语句改，前提是已经进入数据库
alter user root@'localhost' identified by '123456';
# 利用数据库服务SQL语句修改密码信息
mysql> alter user root@'localhost' identified by 'wzy123';
mysql> flush privileges;
# -- 适合于mysql 8.0mysql> update mysql.user set authentication_string=PASSWORD('wzy123') where user='root' and host='localhost';
mysql> flush privileges;
# -- 适合于mysql 5.7
# PASSWORD是一个改密码的函数mysql> set password for 'root'@'localhost'=PASSWORD('wzy123');
mysql> flush privileges;
# -- 适合于mysql 5.6
查看用户密码信息
如图，查看授权表
mysql> select user,host,authentication_string from mysql.user;
+------------------+-----------+------------------------------------------------------------------------+
| user | host | authentication_string |
+------------------+-----------+------------------------------------------------------------------------+
| mysql.infoschema | localhost | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| mysql.session | localhost | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| mysql.sys | localhost | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| root | localhost | $A$005$dC p!W6VI8SpVI YtOOsYvEqPZ4ksiKC2yTXWAfKFAFa3hPoEw0hDduo/D |
+------------------+-----------+------------------------------------------------------------------------+
root密码重置
说明：此次数据库为linux环境二进制部署的mysql8.0.26
1.首先关闭数据库。service mysqld stop…多种方式可以关闭
systemctl stop mysqld
2.安全模式下启动数据库。（安全模式可以免密登录）
/usr/local/mysql/bin/mysqld_safe \
--datadir=/data/3306/data \
--skip-grant-tables --skip-networking# 输出信息：
Logging to '/data/3306/data/db01.err'.
2024-11-04T03:33:46.500373Z mysqld_safe Starting mysqld daemon with databases from /data/3306/data
3.尝试无密码登录成功
[root@db01~]# mysql -uroot
mysql>
3.重置密码信息
❗️此时内存中，并没有授权表信息，所以不能直接改密码。需要把磁盘中的授权表信息写入到内存中，再做修改
# 刷新授权表
mysql> flush privileges;
Query OK, 0 rows affected (0.01 sec)# 修改密码
mysql> alter user root@localhost identified by '123456';
Query OK, 0 rows affected (0.00 sec)
4.重新启动数据库
关闭之前开启的安全模式的数据库进程
pkill mysql
重新启动数据库
systemctl start mysqld
5.登录访问测试
[root@db01~]# mysql -uroot -p123456
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 8
Server version: 8.0.26 MySQL Community Server - GPLCopyright (c) 2000, 2021, Oracle and/or its affiliates.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>
MySQL的用户管理
- 增删改查用户
- 用户信息==用户名+登录的host
查看用户信息
- 查看所有登录的用户，
show processlist
mysql> show processlist;
+----+-----------------+------------------+------+---------+------+------------------------+------------------+
| Id | User | Host | db | Command | Time | State | Info |
+----+-----------------+------------------+------+---------+------+------------------------+------------------+
| 5 | event_scheduler | localhost | NULL | Daemon | 5842 | Waiting on empty queue | NULL |
| 8 | user1 | 10.0.0.170:49194 | NULL | Sleep | 5754 | | NULL |
| 11 | root | localhost | NULL | Query | 0 | init | show processlist |
| 14 | root | 10.0.0.170:49198 | NULL | Sleep | 4482 | | NULL |
+----+-----------------+------------------+------+---------+------+------------------------+------------------+
MySQL配置root远程登录
如果使用的是MySQL初始化完成后的密码，虽然可以实现登录。但是会出现权限不足问题。建议创建一个远程账号
# 可选项，可以忽略
mysqld --initialize-insecure --user=mysql --datadir=/data/3306/data --basedir=/usr/local/mysql
mysql
create user root@'%' identified by '123456';
grant all on *.* to root@'%';
创建用户
db02创建用户
create user user2@'%' identified by 'wzy666';web01使用mariadb客户端尝试远程登录失败
[root@web01~]# mysql -h 10.0.0.51 -uuser1 -pwzy666
ERROR 2059 (HY000): Authentication plugin 'caching_sha2_password' cannot be loaded: /usr/lib64/mysql/plugin/caching_sha2_password.so: cannot open shared object file: No such file or directory原因：MySQL8和mariadb加密方式不一致# MySQL8使用原密码插件，其他客户端可以远程登录
create user user3@'172.16.1.%' identified with mysql_native_password by 'wzy666';
- 查看当前数据库登录用户
mysql> select user();
+----------------+
| user() |
+----------------+
| root@localhost |
+----------------+
1 row in set (0.00 sec)
删除用户，锁用户
方式1： 推荐
drop user user1;方式2： 可能导致删除多个同名用户
delete from mysql.user where user='user2' and host='%';
- 删除多个用户，使用条件表达式where
delete from mysql.user where user='user1' or user='user2';
锁定/解锁用户
直接删除用户有风险，即使后期创建回来，也面临着权限再次设置的问题。当不需要用户时，可以暂时锁定用户，等待一段时间后，确认用户真的不需要了就可以删除用户。
# 锁定
alter user user3@'%' account lock;# 解锁
alter user user3@'%' account unlock;# 登录测试 失败，已被锁
[root@web01~]# mysql -h 10.0.0.51 -uuser3 -pwzy666
ERROR 3118 (HY000): Access denied for user 'user3'@'web01'. Account is locked.
2.查看用户锁定情况，mysql.user的 account_locked 字段Y表示锁定，N表示没有
用户密码的加密插件
现象：
./mysql -utest01 -p123 -h10.0.0.51
Warning: Using a password on the command line interface can be insecure.
ERROR 2059 (HY000): Authentication plugin ‘caching_sha2_password’ cannot be loaded: /usr/local/mysql/lib/plugin/caching_sha2_password.so: cannot open shared object file: No such file or directory
**原因：**新版数据库密码加密插件进行了更新
解决方式：
- 方式1：升级客户端，使客户端加密密码方式支持 caching_sha2_password
- 方式2：降级服务端，使服务端加密密码方式支持 mysql_native_password
查看用户的密码加密方式
1.查看系统默认加密方式
# MySQL8加密方式
mysql> show variables like '%auth%';
+-------------------------------+-----------------------+
| Variable_name | Value |
+-------------------------------+-----------------------+
| default_authentication_plugin | caching_sha2_password |
+-------------------------------+-----------------------+# mariadb加密方式
MariaDB [(none)]> show variables like '%auth%';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| secure_auth | OFF |
+---------------+-------+
1 row in set (0.00 sec)
2.查看每个用户的加密方式
mysql> select user,host,authentication_string,plugin from mysql.user;
+------------------+-----------+------------------------------------------------------------------------+-----------------------+
| user | host | authentication_string | plugin |
+------------------+-----------+------------------------------------------------------------------------+-----------------------+
| user4 | $ | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 | mysql_native_password |
| user1 | % | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 | mysql_native_password |
| user2 | % | $A$005$&pFjeeAB>Q6yPTeTbJMbsJKqXdk6y8cgSpYWn3Y/AByDgrhFaH31I21B | caching_sha2_password |
| user3 | % | *2032C0AE4B6A02A90186A076522B58DCBCA26467 | mysql_native_password |
| user4 | % | *2032C0AE4B6A02A90186A076522B58DCBCA26467 | mysql_native_password |
| user5 | % | *2032C0AE4B6A02A90186A076522B58DCBCA26467 | mysql_native_password |
| mysql.infoschema | localhost | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED | caching_sha2_password |
| mysql.session | localhost | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED | caching_sha2_password |
| mysql.sys | localhost | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED | caching_sha2_password |
| root | localhost | $A$005$LJS<)'E_\V:bzgSSZFmCsgks7ZdFYUqzu.kmMdC3X.rWniJra0gGUCP.r3 | caching_sha2_password |
+------------------+-----------+------------------------------------------------------------------------+-----------------------+
3种使用旧版加密的方式
- 创建用户时使用旧版加密
create user user3@'172.16.1.%' identified with mysql_native_password by 'wzy666';
- 把现有用户的加密方式改为旧版
alter user 'user1'@'%' identified with mysql_native_password by '123456';
- 全局设置使用旧版加密
# 修改数据库服务配置文件信息
[root@xiaoQ-01 ~]# vim /etc/my.cnf
[mysqld]
default_authentication_plugin=mysql_native_password
-- 修改数据库服务配置文件，并在mysqld中区域进行修改# 修改数据库服务配置后重启服务程序
[root@xiaoQ-01 ~]# service mysqld restart
Shutting down MySQL. SUCCESS!
Starting MySQL. SUCCESS! # 登录数据库服务查看加密插件默认配置：
mysql> show variables like '%auth%';
+----------------------------------------+------------------------------+
| Variable_name | Value |
+----------------------------------------+------------------------------+
| default_authentication_plugin | mysql_native_password |
+----------------------------------------+------------------------------+
登录白名单功能
MySQL 的 白名单功能用于限制哪些客户端可以连接到 MySQL 服务器。只有在白名单中的 IP 地址或者网络能够访问数据库，其他的则被拒绝连接。可以提高数据库的安全性，防止未经授权的访问
配置本地登录
使用回环接口 127.0.0.1 只允许本地登录
# 指定网段，只能标准掩码，不支持子网划分
root@'10.0.0.0/24'[root@db01~]# mysql -uloopback -pwzy666 -h 127.0.0.1
提升登录范围
使用通配符 %，表示任意IP地址都可以远程登录mysql
UPDATE mysql.user SET host = '%' WHERE user = 'test01';
使用回环接口 127.0.0.1 只允许本地登录
# 指定网段，只能标准掩码，不支持子网划分
root@'10.0.0.0/24'[root@db01~]# mysql -uloopback -pwzy666 -h 127.0.0.1
提升登录范围
使用通配符 %，表示任意IP地址都可以远程登录mysql
[外链图片转存中…(img-vompddTs-1733159127436)]
UPDATE mysql.user SET host = '%' WHERE user = 'test01';
[外链图片转存中…(img-1ITkpnoQ-1733159127437)]
