Linux下搭建mysql5.7.18

一. 简介
下载路径：https://dev.mysql.com//Downloads/MySQL-5.7/mysql-5.7.21-linux-glibc2.12-x86_64.tar.gz

       系统环境： centOS 7,  mysql 5.7.18

二. 安装步骤
2.1 卸载旧的mysql
2.1.1 删除mysql的安装文件
查询mysql的安装文件：

[root@ali228 ~]# find / -name mysql
/usr/local/env/mysql
/usr/local/env/mysql/mysql
/usr/local/env/mysql/mysql/bin/mysql
/usr/local/env/mysql/mysql/include/mysql
/usr/local/env/mysql/mysql/data/mysql
[root@ali228 ~]#
卸载：

[root@ali228 ~]# rm -rf /usr/local/env/mysql/mysql
[root@ali228 ~]#
2.1.2 删除mysql的配置文件
删除/etc/my.cnf文件

[root@ali228 ~]# rm -rf /etc/my.cnf
删除/etc/init.d/下跟mysql有关的全部文件，一般包括mysql文件或mysqld文件。

[root@ali228 mysql]# rm -rf /etc/init.d/mysql
[root@ali228 mysql]# rm -rf /etc/init.d/mysqlId
2.1.3 删除mysql用户和用户组
[root@ali228 ~]# userdel mysql
userdel: user ‘mysql’ does not exist
至此，卸载OK！

2.2 安装MySQL
2.2.1 下载安装包mysql-5.7.18-linux-glibc2.5-x86_64.tar.gz
安装包路径： https://dev.mysql.com/downloads/mysql/5.7.html#downloads

     上传mysql-5.7.18-linux-glibc2.5-x86_64.tar.gz到/usr/local/env/mysql目录下并解压

[root@ali228 ~]# cd /usr/local/env/mysql/
[root@ali228 mysql]# tar -zxvf mysql-5.7.18-linux-glibc2.5-x86_64.tar.gz
重命名为mysql

2.2.2 添加用户组mysql和用户mysql,并将其添加到mysql用户组中
[root@ali228 mysql]# groupadd mysql
[root@ali228 mysql]# useradd -r -g mysql mysql
注： useradd -r参数表示mysql用户是系统用户，不可用于登录系统。

       useradd -g参数表示把mysql用户添加到mysql用户组中。

2.2.3 检查是否安装了 libaio
[root@baidu64 ~]# rpm -qa | grep libaio
如果没有安装，使用如下命令安装

[root@baidu64 ~]# yum search libaio
2.2.4 配置my.cnf文件
[root@baidu64 ~]# touch /etc/my.cnf
注意：使用默认的644权限和用户，不要做修改；

将如下内容拷贝到里面：

[mysql]  
 
# 设置mysql客户端默认字符集  
 
default-character-set=utf8   
 
socket=/tmp/mysql.sock
 
[mysqld]  
 
#skip-name-resolve  
 
#设置3306端口  
 
port=3306   
 
socket=/tmp/mysql.sock
  
 
# 设置mysql的安装目录 
 
basedir=/usr/local/env/mysql/mysql  
 
# 设置mysql数据库的数据的存放目录 
 
datadir=/usr/local/env/mysql/mysql/data  
 
# 允许最大连接数  
 
max_connections=200  
 
# 服务端使用的字符集默认为8比特编码的latin1字符雿 
 
character-set-server=utf8  
 
# 创建新表时将使用的默认存储引擿 
 
default-storage-engine=INNODB  
 
#lower_case_table_name=1  
 
max_allowed_packet=16M

2.2.5 创建data文件夹
[root@baidu64 mysql]# pwd
/usr/local/env/mysql/mysql
[root@baidu64 mysql]# mkdir data
2.2.6 将mysql目录的所属用户和组改为mysql
[root@baidu64 mysql]# chown -R mysql:mysql ./
2.2.7 初始化mysqld 生成初始化密码
[root@baidu64 mysql]# ./bin/mysqld --initialize --user=mysql --basedir=/usr/local/env/mysql/mysql --datadir=/usr/local/env/mysql/mysql/data
此时，控制台打印如下：

2018-10-24T04:25:13.673365Z 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2018-10-24T04:25:15.808961Z 0 [Warning] InnoDB: New log files created, LSN=45790
2018-10-24T04:25:16.105505Z 0 [Warning] InnoDB: Creating foreign key constraint system tables.
2018-10-24T04:25:16.184776Z 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: cec94f21-d744-11e8-a0b5-fa163ed8e403.
2018-10-24T04:25:16.188372Z 0 [Warning] Gtid table is not ready to be used. Table ‘mysql.gtid_executed’ cannot be opened.
2018-10-24T04:25:16.189074Z 1 [Note] A temporary password is generated for root@localhost: i;lknXwO;5,s
[root@baidu64 mysql]#
结尾： i;lknXwO;5,s 就是初始化的密码。

3 常规配置
3.1 设置开机启动
3.1.1 复制mysql.server脚本到资源目录，并赋予执行权限：
[root@baidu64 mysql]# cp ./support-files/mysql.server /etc/rc.d/init.d/mysqld
[root@baidu64 mysql]# chmod +x /etc/rc.d/init.d/mysqld
3.1.2 将 mysqld 服务加入到系统服务并检测是否生效：
[root@baidu64 mysql]# chkconfig --add mysqld
[root@baidu64 mysql]# chkconfig --list mysqld

Note: This output shows SysV services only and does not include native
systemd services. SysV configuration data might be overridden by native
systemd configuration.

  If you want to list systemd services use 'systemctl list-unit-files'.
  To see services enabled on particular target use
  'systemctl list-dependencies [target]'.

mysqld 0:off 1:off 2:on 3:on 4:on 5:on 6:off

得到如下结果说明生效。

注：查看启动项：chkconfig --list | grep -i mysql 删除启动项：chkconfig --del mysql

启动mysqld:

[root@baidu64 mysql]# service mysqld start
Starting MySQL.Logging to ‘/usr/local/env/mysql/mysql/data/baidu64.err’.
[ OK ]

3.2 配置环境变量
3.2.1 打开/etc/profile配置文件，添加如下内容：

#mysql环境变量
PATH=$PATH:/soft/mysql/bin
export PATH

3.2.2 执行命令，使其生效：
[root@baidu64 mysql]# source /etc/profile
3.2.3 校验是否成功：
[root@baidu64 mysql]# echo $PATH
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/home/env/jdk/jdk8/jdk1.8.0_171/bin:/root/bin:/home/env/jdk/jdk8/jdk1.8.0_171/bin:/usr/local/env/mysql/mysql/bin

mysql无密码登录
在 etc/my.cnf 添加 skip-grant-tables

3.5.3 重启mysql服务
[root@baidu64 mysql]# service mysql restart
Redirecting to /bin/systemctl restart mysql.service
3.5.4 无密码登录mysql
注意: 此时登录不带p参数：

[root@baidu64 mysql]# mysql -u root
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 3
Server version: 5.7.18 MySQL Community Server (GPL)

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>
3.5.5 再次修改mysql密码：
mysql> use mysql;
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 mysql.user set authentication_string=password(‘123456’) where user=‘root’ ;
Query OK, 1 row affected, 1 warning (0.00 sec)
Rows matched: 2 Changed: 1 Warnings: 1

mysql> use mysql;
mysql>update mysql.user set authentication_string=password('123456') where user='root';
mysql> flush privileges;
mysql> quit

mysql>
3.5.6 然后将my.cnf无密码登录配置去掉（就是上面刚加的那句话）
3.5.7 退出mysql,并重启：
mysql> quit
Bye
[root@baidu64 mysql]# service mysql restart
Redirecting to /bin/systemctl restart mysql.service
[root@baidu64 mysql]#
3.5.8 再次使用navicat连接：

如果服务器上能登录，远程连接不上，请参考下列步骤：

step 1：登入mysql监视器，通过命令: mysql -uroot -p

step 2.：根据提示输入密码

step 3: 选择mysql数据库，通过命令：use mysql;

step 4: 通过命令：select host,user from user;

step 5：修改root用户的连接权限的主机范围为任一主机，执行命令：update user set host='%' where user='root';

step 6:  再查看root用户的连接权限：select host,user from user;

然后执行如下命令：
1. GRANT ALL PRIVILEGES ON *.* TO 'myuser'@'%' IDENTIFIED BY 'mypassword' WITH GRANT OPTION;
例如 GRANT ALL PRIVILEGES ON *.* TO 'root'@'%' IDENTIFIED BY '123456' WITH GRANT OPTION;
3.  FLUSH PRIVILEGES;

如果修改完权限后你还是远程连接不上mysql数据库，那就是需要重启一下mysql服务器，执行命令：systemctl restart mysqld

如此 OK！