RHEL 7.8 64bit MYSQL linux-generic 8.0.20 初始化安装

1. 准备最基础信息的my.cnf

本案例my.cnf配置文件是最基础的初始化配置文件，只能保证mysql服务正常开启，并不适用生产环境，
关于更多关于buffer、logfile等性能参数需要根据主机的CPU、MEM/硬盘等硬件环境进行后续相应优化配置

系统版本
[root@mysql~]# cat /etc/redhat-release 
----Red Hat Enterprise Linux Server release 7.8 (Maipo)
MySQL版本
---MySQL-mysql-8.0.20

---注：如果使用CentOS 8.0以上在执行mysql命令登录时会报错以下错误:
mysql: error while loading shared libraries: libtinfo.so.5: cannot open shared object file: No such file or directory，
需要使用ln -s重新定义lib库软连接解决报错问题
[root@mysql ~]#sudo ln -s /usr/lib64/libtinfo.so.6.1 /usr/lib64/libtinfo.so.5

--安装之前检查系统有没有mariadb客户端，如果有建议删除
[root@mysql]# rpm -qa |grep mariadb
mariadb-5.5.65-1.el7.x86_64
mariadb-libs-5.5.65-1.el7.x86_64

如果不删除使用客户端连接可能会出现以下显示情况
[root@mysql]# mysql -uroot -h127.0.0.1  -p
Enter password: 
Welcome to the MariaDB monitor.  Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.7.31-log MySQL Community Server (GPL)
Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

MySQL [(none)]>

删除命令如下
[root@mysql]# rpm -e  --nodeps mariadb-5.5.65-1.el7.x86_64  mariadb-libs-5.5.65-1.el7.x86_64 
warning: /etc/my.cnf saved as /etc/my.cnf.rpmsave

1.1. 准备my.cnf 配置文件
[root@mysql ~]#vi /etc/my.cnf 

[mysqld]

##SERVER ID
server_id=1

##data directory
datadir=/mysql/data

##SOCKET & pid
socket=/tmp/mysql.sock
pid-file=/tmp/mysql.pid

##logfile
log-error=/mysql/log/error.log
log_bin = /mysql/binlog/mysql-bin
binlog_format=ROW

##TRX mode
transaction-isolation = READ-COMMITTED


1.2 环境变量配置
[root@mysql ~]# pwd
/root

1.2.1 添加以下环境变量
[root@mysql ~]# vi .bash_profile 

PATH=$PATH:/usr/local/mysql/bin

1.2.2 source 生效当前环境变量
[root@mysql ~]# source  .bash_profile 

1.2.3 查看生效结果 mysql的环境变量已经在PATH里了
[root@mysql ~]#echo  $PATH
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/root/bin:/usr/local/mysql/bin:/usr/local/mysql/bin:/root/bin:/usr/local/mysql/bin:/usr/local/mysql/bin

2.mysql 数据用户、文件目录初始化

2.1 创建mysql用户、组

[root@mysql~]#groupadd mysql

[root@mysql~]#useradd -r -g mysql -s /bin/false mysql

2.2 创建mysql数据文件目录权限

[root@mysql~]# mkdir -p /mysql/data  
[root@mysql~]# mkdir -p /mysql/log/
[root@mysql~]# mkdir -p /mysql/binlog/
[root@mysql~]# chown -R mysql:mysql  /mysql
[root@mysql~]# chmod -R 775 /mysql/


2.2.1查看权限

[root@mysql /]# ls -ld /mysql/
drwxrwxr-x.  5 mysql mysql 41 Oct 25 21:35 /mysql/


2.3 解压安装mysql server

2.3.1 将下载好的mysql-8.0.20-linux-glibc2.12-x86_64.tar.xz文件放在目录/usr/local

[root@mysql local]#cd /usr/local

2.3.2 解压mysql压缩文件

[root@mysql local]#tar xvf mysql-8.0.20-linux-glibc2.12-x86_64.tar.xz

2.3.3 创建mysql软链接文件
[root@mysql local]#ln -s    mysql-8.0.20-linux-glibc2.12-x86_64   mysql

2.3.4  创建mysql-file 赋权限
[root@mysql local]#cd mysql

[root@mysql mysql]#mkdir mysql-files

[root@mysql mysql]#chown mysql:mysql mysql-files

[root@mysql mysql]#chmod 750 mysql-files



3.初始化mysql server

[root@mysql mysql]#cd /usr/local/mysql

[root@mysql mysql]#bin/mysqld --initialize --user=mysql

配置ssl
[root@mysql mysql]#bin/mysql_ssl_rsa_setup

使用mysqld_safe启动mysql

[root@mysql mysql]#bin/mysqld_safe --user=mysql &

2020-10-25T13:57:57.972091Z mysqld_safe Logging to '/mysql/log/error.log'.
2020-10-25T13:58:58.008556Z mysqld_safe Starting mysqld daemon with databases from /mysql/data

查看3306端口,有3306端口证明mysql已经启动
[root@mysql mysql]# ss -ln |grep 3306
tcp    LISTEN     0      70     [::]:33060              [::]:*                  
tcp    LISTEN     0      128    [::]:3306               [::]:*

3.2 拷贝mysql.server启动文件到/etc/init.d/
[root@mysql mysql]#cp support-files/mysql.server /etc/init.d/mysql.server


4.查看密码
error log 目录在/mysql/log/中，进入/mysql/log/也可以查看error.log查找mysql初始化密码

[root@mysql]#cd /mysql/log/
[root@mysql log]# more error.log 
2020-10-25T13:58:13.679884Z 0 [System] [MY-013169] [Server] /usr/local/mysql-8.0.20-linux-glibc2.12-x86_64/bin/mysqld (mysqld 8.0.20) initializing of server in progress as pro
cess 14924
2020-10-25T13:58:13.693343Z 1 [System] [MY-013576] [InnoDB] InnoDB initialization has started.
2020-10-25T13:58:14.402699Z 1 [System] [MY-013577] [InnoDB] InnoDB initialization has ended.
2020-10-25T13:58:15.799133Z 6 [Note] [MY-010454] [Server] A temporary password is generated for root@localhost: Ern8uu_RY!9r

密码是随机码----> Ern8uu_RY!9r

5.登录mysql

使用rn8uu_RY!9r密码登录
[root@ mysql]# mysql -uroot -h127.0.0.1 -p
Enter password:
 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 8
Server version: 8.0.20
Copyright (c) 2000, 2020, Oracle and/or its affiliates. All rights reserved.

执行show database时会提示修改初始密码

mysql> show databases;
ERROR 1820 (HY000): You must reset your password using ALTER USER statement before executing this statement.


6.修改初始化root密码
mysql密码的维度是用户名+主机，修改密码是需要根据用户名和主机的维度来一起修改

mysql> alter user 'root'@'localhost' identified by 'mysql123';
Query OK, 0 rows affected (0.01 sec)

mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)

6.使用新修改的密码登录mysql

[root@ mysql]# mysql -uroot -h127.0.0.1 -p mysql123
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 8
Server version: 8.0.20
Copyright (c) 2000, 2020, 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> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sys                |
+--------------------+
4 rows in set (0.00 sec)

到此，mysql server最基本的初始化就完成了