linux 安装mysql 5.7.21详解以及安装过程中所遇问题解决

Posted 2020-10-23

在安装过程中所遇到的问题有：
1、my-default.cnf文件找不到
2、mysql启动报错
3、mysql临时密码无法登录

安装环境centos 6.0
下载数据库：
[[email protected] src]# pwd
/usr/local/src #下载文件存放路径（个人原因，可随意。）
[[email protected] src]#
wget https://cdn.mysql.com//Downloads/MySQL-5.7/mysql-5.7.21-linux-glibc2.12-x86_64.tar.gz
[[email protected] src]# tar -zxvf mysql-5.7.21-linux-glibc2.12-x86_64.tar.gz #解压
[[email protected] src]# mv mysql-5.7.21-linux-glibc2.12-x86_64 mysql
#更改文件名
卸载旧版本：
[[email protected] src]# rpm -qa |grep mysql
mysql-5.1.47-4.el6.x86_64
mysql-libs-5.1.47-4.el6.x86_64
mysql-devel-5.1.47-4.el6.x86_64
[[email protected] src]# rpm -e --nodeps mysql-5.1.47-4.el6.x86_64
[[email protected] src]# rpm -e --nodeps mysql-libs-5.1.47-4.el6.x86_64
[[email protected] src]# rpm -e --nodeps mysql-devel-5.1.47-4.el6.x86_64
[[email protected] src]# rpm -qa |grep mysql
[[email protected] src]#

创建数据库目录以及用户和组：
[[email protected] src]#mkdir /data
[[email protected] src]#mkdir /data/mysqldata #数据存放目录
[[email protected] src]#groupadd mysql #创建mysql组
[[email protected] src]#useradd -r -s /sbin/nologin -g mysql mysql -d /usr/local/src/mysql #添加mysql用户使其shell模式为nologin（禁止登录），
[[email protected] mysql]# chown -R mysql .
[[email protected] mysql]# chgrp -R mysql .
[[email protected] mysql]#chown -R mysq /data/mysqldata
安装前先安装numactl组件，或者会报错：bin/mysqld: error while loading shared libraries: libnuma.so.1
[[email protected] mysql]# yum -y install numactl
（可以使用本地CD yum源进行安装，前提是搭建好后。）
配置参数:
[[email protected] src]# cd mysql
[[email protected] mysql]# bin/mysqld --initialize --user=mysql --basedir=/usr/local/src/mysql --datadir=/data/mysqldata/ #配置参数
2018-01-31T08:41:32.144065Z 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2018-01-31T08:41:34.501273Z 0 [Warning] InnoDB: New log files created, LSN=45790
2018-01-31T08:41:34.943351Z 0 [Warning] InnoDB: Creating foreign key constraint system tables.
2018-01-31T08:41:35.016168Z 0 [Warning] No existing UUID has been found, so we assume that this is the first time that this server has been started. Generating a new UUID: 8b673fc1-0662-11e8-a70a-000c298536ba.
2018-01-31T08:41:35.021358Z 0 [Warning] Gtid table is not ready to be used. Table ‘mysql.gtid_executed‘ cannot be opened.
2018-01-31T08:41:35.025019Z 1 [Note] A temporary password is generated for [email protected]: dhaMrqAVZ5-C {最后的[email protected]：后面为临时密码（在我安装过程中感觉没有，登录不了。)}
--basedir=/usr/local/src/mysql #mysql文件所在目录
--datadir=/data/mysqldata/ #数据库存放目录

[[email protected] mysql]# bin/mysql_ssl_rsa_setup --datadir=/data/mysqldata/
#配置参数

修改系统配置文件:

在support-files目录未发现my-default.cnf文件,所以只能手动创建了。
[[email protected] support-files]# vim /etc/my.cnf （创建my.cnf，将以下代码复制进去，记得下面几个目录需要自己手动修改为自己定义的目录）

[client]
port = 3306
socket = /tmp/mysql.sock

[mysqld]
character_set_server=utf8
init_connect=‘SET NAMES utf8‘
basedir=/usr/local/src/mysql #文件存放目录
datadir=/data/mysqldata/ #数据库存放目录
socket=/usr/local/src/mysql/mysql.sock
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid
lower_case_table_names = 1

sql_mode=STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION
max_connections=5000

default-time_zone = ‘+8:00‘

[[email protected] support-files]# cp mysql.server /etc/init.d/mysql
[[email protected] support-files]# vim /etc/init.d/mysql
修改/etc/init.d/mysqld在basedir和datadir后填入文件存放路径和数据存放路径

启动mysql：
[[email protected] mysql]# bin/mysqld_safe --user=mysql & #检测

[[email protected] run]# /etc/init.d/mysql start （这里会报错，因为找不到mysqld文件夹，所以要创建并赋予权限。）


[[email protected] mysql]# cd /var/run/
[[email protected] run]# mkdir mysqld
[[email protected] run]# chown -R mysql mysqld
[[email protected] run]# chgrp -R mysql mysqld
[[email protected] run]# /etc/init.d/mysql start
Starting MySQL... [ OK ]

登录mysql已经修改密码：
由于试过使用mysql临时密码无法登录，所以以下直接进入配置.
修改/etc/my.cnf文件
在[mysqld]下面添加“skip-grant-tables”

（skip-grant-tables命令为跳过验证，直接登录。个人认为好比linux的单用户模式，来进行mysql的密码修改。）
重启mysql

在命令行中输入mysql进行登录

mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
+--------------------+
4 rows in set (0.00 sec)

mysql> USE mysql; #选择数据库
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed
mysql> update user set authentication_string=password(‘123abc‘) where user=‘root‘;
Query OK, 0 rows affected, 1 warning (0.00 sec)
Rows matched: 1 Changed: 0 Warnings: 1

mysql> flush privileges; #刷新权限
Query OK, 0 rows affected (0.00 sec)

mysql> quit;
Bye
重新登录mysql
[[email protected] run]#mysql -uroot -p123abc

最后一步注销my.cnf中的“skip-grant-tables”