以下升级过程使用root用户执行

1 安装 mysql8.0.29

❯ yum install mysql-server

2 删除mysql8默认数据库目录，复制mysql5.7数据库目录到mysql8默认目录下

❯ rm -rf /var/lib/mysql

❯ cp -a /var/lib/mysql57/data /var/lib/mysql

注意：这里cp时使用-a保持源文件的属性，否则需要手动修改文件属性。

❯ rm -rf mysql/auto.cnf

❯ rm -rf mysql/ib_logfile*

删除mysql5.7的日志归档及auto.cnf配置文件，否则将因文件被占用无法启动。

❯ setenforce 0

关闭selinux,否则将报./ibdata1权限被拒绝错误，错误如下：

os_file_get_status() failed on './ibdata1'. Can't determine file permissions

3 启动mysql8服务自动升级mysql5.7

❯ systemctl start mysqld

再开一个终端，查看升级过程日志

❯ tail -f /var/log/mysql/mysqld.log

2023-10-18T06:20:29.538734Z 0 [System] [MY-013172] [Server] Received SHUTDOWN from user . Shutting down mysqld (Version: 8.0.29).

2023-10-18T06:20:30.590284Z 0 [System] [MY-010910] [Server] /usr/libexec/mysqld: Shutdown complete (mysqld 8.0.29) Source distribution.

2023-10-18T06:22:24.150157Z 0 [Warning] [MY-011070] [Server] 'Disabling symbolic links using --skip-symbolic-links (or equivalent) is the default. Consider not using t

his option as it' is deprecated and will be removed in a future release.

2023-10-18T06:22:24.151800Z 0 [System] [MY-010116] [Server] /usr/libexec/mysqld (mysqld 8.0.29) starting as process 3653206

2023-10-18T06:22:24.268962Z 0 [Warning] [MY-010075] [Server] No existing UUID has been found, so we assume that this is the first time that this server has been starte

d. Generating a new UUID: b3aad854-6d7e-11ee-a61f-d05099d4fa2e.

2023-10-18T06:22:24.293287Z 1 [System] [MY-011012] [Server] Starting upgrade of data directory.

（开始升级数据文件目录）

2023-10-18T06:22:24.293337Z 1 [System] [MY-013576] [InnoDB] InnoDB initialization has started.

2023-10-18T06:22:28.166543Z 1 [System] [MY-013577] [InnoDB] InnoDB initialization has ended.

2023-10-18T06:24:32.504481Z 2 [System] [MY-011003] [Server] Finished populating Data Dictionary tables with data.

2023-10-18T06:24:50.541998Z 5 [System] [MY-013381] [Server] Server upgrade from '50700' to '80029' started.

（升级服务）

2023-10-18T06:26:24.674418Z 5 [System] [MY-013381] [Server] Server upgrade from '50700' to '80029' completed.

2023-10-18T06:26:25.612995Z 0 [Warning] [MY-010068] [Server] CA certificate ca.pem is self signed.

2023-10-18T06:26:25.613033Z 0 [System] [MY-013602] [Server] Channel mysql_main configured to support TLS. Encrypted connections are now supported for this channel.

2023-10-18T06:26:25.768956Z 0 [System] [MY-011323] [Server] X Plugin ready for connections. Bind-address: '::' port: 33060, socket: /var/lib/mysql/mysqlx.sock

2023-10-18T06:26:25.769015Z 0 [System] [MY-010931] [Server] /usr/libexec/mysqld: ready for connections. Version: '8.0.29' socket: '/var/lib/mysql/mysql.sock' port: 3

306 Source distribution.

4 查看升级后的数据库

❯ mysql -u root -p

Enter password:

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

Your MySQL connection id is 12

Server version: 8.0.29 Source distribution

Copyright (c) 2000, 2022, 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> show databases;

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

| Database |

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

| awshlp63 |

| datian_water |

| ecology |

| information_schema |

| kk-reservoir |

| mysql |

| performance_schema |

| renren_security |

| sys |

| xmhospital |

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

10 rows in set (0.00 sec)

mysql>

致此mysql5.7升级至mysql8.0.29完成。