背景：
一般專案系統開發都是在windows平臺上，而一旦專案系統開發完成，出於安全性、穩定性的考慮，資料庫伺服器、應用伺服器都會安裝在Linux平臺上，本篇講解的就是如何在Linux的發行版centos7安裝MySQL資料庫。這裡僅僅是做實驗，所以是在虛擬機器上安裝的centos7之上安裝MySQL。

安裝步驟：
1、上傳下載到的MySQL tar包到虛擬機器centos上並解壓到指定的目錄下

[[email protected] ~]# ll
總用量 186968
-rw——-. 1 root root 1740 12月 4 19:00 anaconda-ks.cfg
-rw-r–r–. 1 root root 191447040 12月 9 09:59 MySQL-5.5.48-1.linux2.6.x86_64.rpm-bundle.tar
drwxr-xr-x. 3 root root 4096 12月 9 10:00 soft

[[email protected] ~]# tar -xvf MySQL-5.5.48-1.linux2.6.x86_64.rpm-bundle.tar -
C soft/mysql/

MySQL-client-5.5.48-1.linux2.6.x86_64.rpm
MySQL-shared-compat-5.5.48-1.linux2.6.x86_64.rpm
MySQL-test-5.5.48-1.linux2.6.x86_64.rpm
MySQL-server-5.5.48-1.linux2.6.x86_64.rpm
MySQL-embedded-5.5.48-1.linux2.6.x86_64.rpm
MySQL-devel-5.5.48-1.linux2.6.x86_64.rpm
MySQL-shared-5.5.48-1.linux2.6.x86_64.rpm

[[email protected] ~]# cd soft/mysql/
[[email protected] mysql]# ll
總用量 186960
-rw-r–r–. 1 7155 wheel 17855952 1月 17 2016 MySQL-client-5.5.48-1.linux2.6.x86_64.rpm
-rw-r–r–. 1 7155 wheel 6522838 1月 17 2016 MySQL-devel-5.5.48-1.linux2.6.x86_64.rpm
-rw-r–r–. 1 7155 wheel 67718815 1月 17 2016 MySQL-embedded-5.5.48-1.linux2.6.x86_64.rpm
-rw-r–r–. 1 7155 wheel 50372369 1月 17 2016 MySQL-server-5.5.48-1.linux2.6.x86_64.rpm
-rw-r–r–. 1 7155 wheel 2038979 1月 17 2016 MySQL-shared-5.5.48-1.linux2.6.x86_64.rpm
-rw-r–r–. 1 7155 wheel 5180005 1月 17 2016 MySQL-shared-compat-5.5.48-1.linux2.6.x86_64.rpm
-rw-r–r–. 1 7155 wheel 41748495 1月 17 2016 MySQL-test-5.5.48-1.linux2.6.x86_64.rpm

2、解除安裝centos7自帶的mariadb，不然安裝MySQL的時候會和mariadb檔案相沖突導致安裝不成功。

[[email protected] mysql]# rpm -qa | grep mariadb
mariadb-libs-5.5.56-2.el7.x86_64
[[email protected] mysql]# rpm -e mariadb-libs-5.5.56-2.el7.x86_64
–nodeps

3、安裝MySQL服務端和客戶端

[[email protected] mysql]# rpm -ivh MySQL-server-5.5.48-1.linux2.6.x86_64.rpm

[[email protected] mysql]# rpm -ivh MySQL-client-5.5.48-1.linux2.6.x86_64.rpm

tips
one:必須進到rpm所在目錄進行安裝，不然會報錯說找不到rpm

two:安裝服務端會出現提示，提示很重要，很重要，很重要。涉及到MySQL的密碼及其它的一些工作。

PLEASE REMEMBER TO SET A PASSWORD FOR THE MySQL root USER !
To do so, start the server, then issue the following commands:

/usr/bin/mysqladmin -u root password ‘new-password’
/usr/bin/mysqladmin -u root -h localhost.localdomain password ‘new-password’

Alternatively you can run:
/usr/bin/mysql_secure_installation

which will also give you the option of removing the test
databases and anonymous user created by default. This is
strongly recommended for production servers.

所以安裝完客戶端之後，必須按照以上的提示修改密碼：

[[email protected] mysql]# /usr/bin/mysql_secure_installation

問題：

Enter current password for root (enter for none):
ERROR 2002 (HY000): Can’t connect to local MySQL server through socket ‘/var/lib/mysql/mysql.sock’ (2)

原因：檢視MySQL啟動狀態，可以看到MySQL服務沒有開啟，所以修改密碼前必須先開啟MySQL服務

[[email protected] mysql]# service mysql status
ERROR! MySQL is not running

4、開啟MySQL服務

[[email protected] mysql]# service mysql start
[[email protected] mysql]# service mysql status
SUCCESS! MySQL running (1783)

5、修改密碼

[[email protected] mysql]# /usr/bin/mysql_secure_installation

NOTE: RUNNING ALL PARTS OF THIS SCRIPT IS RECOMMENDED FOR ALL MySQL
SERVERS IN PRODUCTION USE! PLEASE READ EACH STEP CAREFULLY!

In order to log into MySQL to secure it, we’ll need the current
password for the root user. If you’ve just installed MySQL, and
you haven’t set the root password yet, the password will be blank,
so you should just press enter here.

Enter current password for root (enter for none):
OK, successfully used password, moving on…

Setting the root password ensures that nobody can log into the MySQL
root user without the proper authorisation.

Set root password? [Y/n] y
New password:
Re-enter new password:
Password updated successfully!
Reloading privilege tables..
… Success!

By default, a MySQL installation has an anonymous user, allowing anyone
to log into MySQL without having to have a user account created for
them. This is intended only for testing, and to make the installation
go a bit smoother. You should remove them before moving into a
production environment.

Remove anonymous users? [Y/n] y
… Success!

Normally, root should only be allowed to connect from ‘localhost’. This
ensures that someone cannot guess at the root password from the network.

Disallow root login remotely? [Y/n] n
… skipping.

By default, MySQL comes with a database named ‘test’ that anyone can
access. This is also intended only for testing, and should be removed
before moving into a production environment.

Remove test database and access to it? [Y/n] y
- Dropping test database…
… Success!
- Removing privileges on test database…
… Success!

Reloading the privilege tables will ensure that all changes made so far
will take effect immediately.

Reload privilege tables now? [Y/n] y
… Success!

Cleaning up…

All done! If you’ve completed all of the above steps, your MySQL
installation should now be secure.

Thanks for using MySQL!

6、登入測試

[[email protected] mysql]# mysql -uroot -proot

7、開啟遠端MySQL資料庫訪問，這裡測試我們的主機windows的客戶端去連線虛擬機器上centos上的MySQL資料庫。

問題：無法訪問

原因：centos7的防火牆設定、MySQL資料庫遠端訪問的授權設定

[[email protected] mysql]# firewall-cmd –state
running
[[email protected] mysql]# firewall-cmd –list-ports
[[email protected] mysql]#

[[email protected] mysql]# mysql -uroot -proot
mysql> select * from mysql.user where user=’root’ \G;

***************** 1. row *****************
Host: localhost
User: root
Password: *81F5E21E35407D884A6CD4A731AEBFB6AF209E1B
Select_priv: Y
Insert_priv: Y
Update_priv: Y
Delete_priv: Y
Create_priv: Y
Drop_priv: Y
Reload_priv: Y
Shutdown_priv: Y
Process_priv: Y
File_priv: Y
Grant_priv: Y
References_priv: Y
Index_priv: Y
Alter_priv: Y
Show_db_priv: Y
Super_priv: Y
Create_tmp_table_priv: Y
Lock_tables_priv: Y
Execute_priv: Y
Repl_slave_priv: Y
Repl_client_priv: Y
Create_view_priv: Y
Show_view_priv: Y
Create_routine_priv: Y
Alter_routine_priv: Y
Create_user_priv: Y
Event_priv: Y
Trigger_priv: Y
Create_tablespace_priv: Y
ssl_type:
ssl_cipher:
x509_issuer:
x509_subject:
max_questions: 0
max_updates: 0
max_connections: 0
max_user_connections: 0
plugin:
authentication_string:
***************** 2. row *****************
Host: localhost.localdomain
User: root
Password: *81F5E21E35407D884A6CD4A731AEBFB6AF209E1B
Select_priv: Y
Insert_priv: Y
Update_priv: Y
Delete_priv: Y
Create_priv: Y
Drop_priv: Y
Reload_priv: Y
Shutdown_priv: Y
Process_priv: Y
File_priv: Y
Grant_priv: Y
References_priv: Y
Index_priv: Y
Alter_priv: Y
Show_db_priv: Y
Super_priv: Y
Create_tmp_table_priv: Y
Lock_tables_priv: Y
Execute_priv: Y
Repl_slave_priv: Y
Repl_client_priv: Y
Create_view_priv: Y
Show_view_priv: Y
Create_routine_priv: Y
Alter_routine_priv: Y
Create_user_priv: Y
Event_priv: Y
Trigger_priv: Y
Create_tablespace_priv: Y
ssl_type:
ssl_cipher:
x509_issuer:
x509_subject:
max_questions: 0
max_updates: 0
max_connections: 0
max_user_connections: 0
plugin:
authentication_string:
***************** 3. row *****************
Host: 127.0.0.1
User: root
Password: *81F5E21E35407D884A6CD4A731AEBFB6AF209E1B
Select_priv: Y
Insert_priv: Y
Update_priv: Y
Delete_priv: Y
Create_priv: Y
Drop_priv: Y
Reload_priv: Y
Shutdown_priv: Y
Process_priv: Y
File_priv: Y
Grant_priv: Y
References_priv: Y
Index_priv: Y
Alter_priv: Y
Show_db_priv: Y
Super_priv: Y
Create_tmp_table_priv: Y
Lock_tables_priv: Y
Execute_priv: Y
Repl_slave_priv: Y
Repl_client_priv: Y
Create_view_priv: Y
Show_view_priv: Y
Create_routine_priv: Y
Alter_routine_priv: Y
Create_user_priv: Y
Event_priv: Y
Trigger_priv: Y
Create_tablespace_priv: Y
ssl_type:
ssl_cipher:
x509_issuer:
x509_subject:
max_questions: 0
max_updates: 0
max_connections: 0
max_user_connections: 0
plugin:
authentication_string:
***************** 4. row *****************
Host: ::1
User: root
Password: *81F5E21E35407D884A6CD4A731AEBFB6AF209E1B
Select_priv: Y
Insert_priv: Y
Update_priv: Y
Delete_priv: Y
Create_priv: Y
Drop_priv: Y
Reload_priv: Y
Shutdown_priv: Y
Process_priv: Y
File_priv: Y
Grant_priv: Y
References_priv: Y
Index_priv: Y
Alter_priv: Y
Show_db_priv: Y
Super_priv: Y
Create_tmp_table_priv: Y
Lock_tables_priv: Y
Execute_priv: Y
Repl_slave_priv: Y
Repl_client_priv: Y
Create_view_priv: Y
Show_view_priv: Y
Create_routine_priv: Y
Alter_routine_priv: Y
Create_user_priv: Y
Event_priv: Y
Trigger_priv: Y
Create_tablespace_priv: Y
ssl_type:
ssl_cipher:
x509_issuer:
x509_subject:
max_questions: 0
max_updates: 0
max_connections: 0
max_user_connections: 0
plugin:
authentication_string:
4 rows in set (0.00 sec)

從以上結果可以看到：
防火牆處於開啟狀態且沒有開啟任何埠可以訪問
MySQL資料庫查詢結果列Host的值，並沒有是%或者指定遠端主機名或ip地址，所以並沒有授權遠端訪問登入設定。

解決：原因找到了之後，就好解決了。

開啟MySQL資料庫遠端訪問許可權

[[email protected] mysql]# mysql -uroot -proot
mysql> GRANT ALL PRIVILEGES ON . TO ‘root’@’%’ IDENTIFIED BY ‘root’ WITH GRANT OPTION; FLUSH PRIVILEGES;

再次查詢MySQL資料庫遠端訪問是否授權：

mysql> select * from mysql.user where user=’root’ \G;

可以看到多了一條記錄HOST值為：%，說明授權了。

***************** 5. row *****************
Host: %
User: root
Password: *81F5E21E35407D884A6CD4A731AEBFB6AF209E1B
Select_priv: Y
Insert_priv: Y
Update_priv: Y
Delete_priv: Y
Create_priv: Y
Drop_priv: Y
Reload_priv: Y
Shutdown_priv: Y
Process_priv: Y
File_priv: Y
Grant_priv: Y
References_priv: Y
Index_priv: Y
Alter_priv: Y
Show_db_priv: Y
Super_priv: Y
Create_tmp_table_priv: Y
Lock_tables_priv: Y
Execute_priv: Y
Repl_slave_priv: Y
Repl_client_priv: Y
Create_view_priv: Y
Show_view_priv: Y
Create_routine_priv: Y
Alter_routine_priv: Y
Create_user_priv: Y
Event_priv: Y
Trigger_priv: Y
Create_tablespace_priv: Y
ssl_type:
ssl_cipher:
x509_issuer:
x509_subject:
max_questions: 0
max_updates: 0
max_connections: 0
max_user_connections: 0
plugin:
authentication_string: NULL
5 rows in set (0.00 sec)

新增MySQL埠執行遠端訪問

firewall-cmd –zone=public –add-port=3306/tcp –permanent

查詢防火牆開放的埠：

[[email protected] mysql]# firewall-cmd –list-ports
3306/tcp

到這裡，主機MySQL客戶端就可以順利連線centos7的MySQL資料庫了。

總結：
本篇主要講述了centos7安裝MySQL資料庫，前提是centos的版本和MySQL的版本必須一致才能按照以上的方法，因為不同版本的Linux、MySQL只有其中一個不同，安裝的方式就有可能不一樣。

安裝MySQL資料庫：
1、採用的是rpm安裝

2、安裝前需解除安裝掉centos7自帶的mariadb,MariaDB資料庫管理系統是MySQL的一個分支，不然安裝的時候會互相沖突導致安裝不成功。

3、安裝
rpm -ivh MySQL-server-5.5.48-1.linux2.6.x86_64.rpm
rpm -ivh MySQL-client-5.5.48-1.linux2.6.x86_64.rpm

4、修改密碼前需開啟服務，開啟服務後方可修改密碼

5、本地登入MySQL資料庫，OK沒有問題
遠端主機登入出現無法訪問的情況，需設定防火牆開啟3306埠可訪問
其次，設定本地MySQL資料庫執行遠端主機登入訪問授權。

以上就是安裝的大體步驟，原理是一樣的。

補充
關於解除安裝：
解除安裝步驟：
1、檢視已經安裝的MySQL服務：

[[email protected] mysql]# rpm -qa | grep -i mysql
MySQL-client-5.5.48-1.linux2.6.x86_64
MySQL-server-5.5.48-1.linux2.6.x86_64

2、解除安裝MySQL服務

[[email protected] mysql]# rpm -e MySQL-server-5.5.48-1.linux2.6.x86_64
[[email protected] mysql]# rpm -e MySQL-client-5.5.48-1.linux2.6.x86_64
[[email protected] mysql]# rpm -qa | grep -i mysql
[[email protected] mysql]#

注意：刪除的時候沒有帶.rpm的字尾

3、查詢MySQL相關資料夾

[[email protected] mysql]# find / -name mysql
/etc/selinux/targeted/active/modules/100/mysql
/usr/lib64/mysql
/var/lib/mysql
/var/lib/mysql/mysql
/root/soft/mysql

注意：/root/soft/mysql是我們手動新建用來存放MySQL rpm的，所以並不需要把它解除安裝。

4、刪除MySQL相關資料夾

[[email protected] mysql]# rm -rf /etc/selinux/targeted/active/modules/100/mysql
[[email protected] mysql]# rm -rf /usr/lib64/mysql
[[email protected] mysql]# rm -rf /var/lib/mysql
[[email protected] mysql]# rm -rf /var/lib/mysql/mysql
[[email protected] mysql]# rm -rf /usr/lib64/mysql

5、重新安裝

[[email protected] mysql]# rpm -ivh MySQL-server-5.5.48-1.linux2.6.x86_64.rpm
[[email protected] mysql]# rpm -ivh MySQL-client-5.5.48-1.linux2.6.x86_64.rpm

接下來的流程就和上面的安裝一樣了。