一台服務器多實例 MySQL 做主從復制

 

在一台服務器上開兩個端口的mysql（3306、3307），做成主從復制環境

1）安裝mysql（安裝過程這里就不做過多介紹）
參考：http://www.cnblogs.com/kevingrace/p/6109679.html
 
本文在一台服務器上做主從實驗
主庫：172.29.16.24：3306
從庫：172.29.16.24：3307
 
主從庫的安裝目錄分別為/usr/local/mysql3306、/usr/local/mysql3307
主從庫的數據目錄分別為/data/mysql3306、/data/mysql3307
主從庫的登錄密碼都為123456
 
兩個實例的my.cnf里不一樣的配置部分
端口不一樣！另外：server-id一定不能一樣，最好用端口號來標明server-id，一個是3306，一個是3307
其他內容配置一樣，主庫一定要開啟binlog日志功能，從庫可以開啟，也可以不開啟）
[root@radius01 ~]# cat /usr/local/mysql3306/my.cnf |grep mysql3306
socket = /usr/local/mysql3306/var/mysql.sock
socket = /usr/local/mysql3306/var/mysql.sock
basedir = /usr/local/mysql3306/
datadir = /data/mysql3306/data
pid-file = /data/mysql3306/data/mysql.pid
log_error = /data/mysql3306/data/mysql-error.log
slow_query_log_file = /data/mysql3306/data/mysql-slow.log
 
[root@radius01 ~]# cat /usr/local/mysql3307/my.cnf |grep mysql3307
socket = /usr/local/mysql3307/var/mysql.sock
socket = /usr/local/mysql3307/var/mysql.sock
basedir = /usr/local/mysql3307/
datadir = /data/mysql3307/data
pid-file = /data/mysql3307/data/mysql.pid
log_error = /data/mysql3307/data/mysql-error.log
slow_query_log_file = /data/mysql3307/data/mysql-slow.log
 
注意分別授權
[root@radius01 ~]# chown -R mysql.mysql /usr/local/mysql3306
[root@radius01 ~]# chown -R mysql.mysql /usr/local/mysql3307
[root@radius01 ~]# chown -R mysql.mysql /data/mysql3306/
[root@radius01 ~]# chown -R mysql.mysql /data/mysql3307
 
啟動主從庫
[root@radius01 ~]# nohup /usr/local/mysql3306/bin/mysqld_safe --datadir=/data/mysql3306/data --pid-file=/data/mysql3306/data/mysql.pid &
[root@radius01 ~]# nohup /usr/local/mysql3307/bin/mysqld_safe --datadir=/data/mysql3307/data --pid-file=/data/mysql3307/data/mysql.pid &
[root@radius01 ~]# lsof -i:3306
COMMAND   PID  USER   FD   TYPE DEVICE SIZE/OFF NODE NAME
mysqld  28617 mysql   19u  IPv4 838860      0t0  TCP *:mysql (LISTEN)
[root@radius01 ~]# lsof -i:3307
COMMAND   PID  USER   FD   TYPE DEVICE SIZE/OFF NODE NAME
mysqld  29538 mysql   19u  IPv4 839401      0t0  TCP *:opsession-prxy (LISTEN)
 
注意，當一台服務器上安裝了多個實例的mysql的時候，直接登錄mysql的時候，記住要在登錄命令中跟上對應的sock路徑，如下：
[root@radius01 ~]# /usr/local/mysql3306/bin/mysql -p123456 -S /usr/local/mysql3306/var/mysql.sock
......
mysql> select @@port;
+--------+
| @@port |
+--------+
|   3306 |
+--------+
1 row in set (0.00 sec)
 
[root@radius01 ~]# /usr/local/mysql3307/bin/mysql -p123456 -S /usr/local/mysql3307/var/mysql.sock
......
mysql> select @@port;
+--------+
| @@port |
+--------+
|   3307 |
+--------+
1 row in set (0.00 sec)
------------------------------------------------------------------------------------------------------------------------
如果不跟上對應的sock路徑，直接登錄的話會報錯：
[root@radius01 ~]# /usr/local/mysql3306/bin/mysql -p123456
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock'
這樣，如果你如下做軟鏈接：
[root@radius01 ~]# ln -s /usr/local/mysql3306/var/mysql.sock /var/lib/mysql/mysql.sock
或者
[root@radius01 ~]# ln -s /usr/local/mysql3307/var/mysql.sock /var/lib/mysql/mysql.sock
 
那么這樣操作之后，無論是登錄3306端口的mysql，還是登錄3307端口的mysql，里面的操作都是一樣的，即這樣就分不清兩個端口的mysql實例了！
所以還是在登錄各個端口的mysql實例時要跟上對應的sock路徑！

2）部署主從復制環境
先在主庫上操作：
[root@radius01 ~]# /usr/local/mysql3306/bin/mysql -p123456 -S /usr/local/mysql3306/var/mysql.sock
......
mysql> GRANT REPLICATION SLAVE ON *.* TO 'repl'@'172.29.16.%' IDENTIFIED BY 'mycatms';
mysql> flush privileges;
mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000015 |      199 |              |                  |                   |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)
 
 
接着在從庫（即33077端口）上設置主從復制
先在從庫上驗證下是否能使用授予的權限連接主庫
[root@radius01 ~]# /usr/local/mysql3307/bin/mysql -u repl -h 172.29.16.24 -pmycatms -S /usr/local/mysql3306/var/mysql.sock
.....
mysql> select @@port;
+--------+
| @@port |
+--------+
|   3306 |
+--------+
1 row in set (0.00 sec)
 
然后進行主從復制設置
[root@radius01 ~]# /usr/local/mysql3307/bin/mysql -p123456 -S /usr/local/mysql3307/var/mysql.sock  
.......
mysql> select @@port;
+--------+
| @@port |
+--------+
|   3307 |
+--------+
1 row in set (0.00 sec)
mysql> stop slave;
mysql> reset slave;
mysql> change master to master_user='repl', master_password='mycatms', master_host='172.29.16.24',master_port=3306, master_log_file='mysql-bin.000015',master_log_pos=199;
mysql> start slave;
mysql> show slave status \G;
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 172.29.16.24
                  Master_User: repl
                  Master_Port: 3306
                Connect_Retry: 60
              Master_Log_File: mysql-bin.000015
          Read_Master_Log_Pos: 199
               Relay_Log_File: mysql-relay-bin.000002
                Relay_Log_Pos: 283
        Relay_Master_Log_File: mysql-bin.000015
             Slave_IO_Running: Yes
            Slave_SQL_Running: Yes
.......
.......
-------------------------------------------------------------------------------------------------------------------------------------
如果出現下面報錯：
Fatal error: The slave I/O thread stops because master and slave have equal MySQL server UUIDs; these UUIDs must be different for replication to work.
 
原因分析：
mysql 5.6的復制引入了uuid的概念，各個復制結構中的server_uuid得保證不一樣，但是查看到直接copy  data文件夾后server_uuid是相同的，show variables like '%server_uuid%';      
也就是說：
我的實驗環境中的3306端口的mysql實例和3307端口的mysql實例的uuid是一樣的導致的，因為我是直接復制的data數據目錄。如下查看：
[root@radius01 ~]# /usr/local/mysql3306/bin/mysql -p123456 -S /usr/local/mysql3306/var/mysql.sock
.........
mysql> show variables like '%server_uuid%';
+---------------+--------------------------------------+
| Variable_name | Value                                |
+---------------+--------------------------------------+
| server_uuid   | 5509fe69-96b6-11e7-aef5-aaafa07a2e23 |
+---------------+--------------------------------------+
1 row in set (0.00 sec)
 
[root@radius01 ~]# /usr/local/mysql3307/bin/mysql -p123456 -S /usr/local/mysql3307/var/mysql.sock
......
mysql> show variables like '%server_uuid%';
+---------------+--------------------------------------+
| Variable_name | Value                                |
+---------------+--------------------------------------+
| server_uuid   | 5509fe69-96b6-11e7-aef5-aaafa07a2e23 |
+---------------+--------------------------------------+
1 row in set (0.00 sec)
 
解決辦法：
找到3306端口和3307端口的data文件夾下的auto.cnf文件，直接刪除掉，然后重啟各自的mysql即可！重啟后，可以再次生成auto.conf文件（重新生成后的uuid就不一樣了）
[root@radius01 ~]# rm -rf /data/mysql3306/data/auto.cnf
[root@radius01 ~]# rm -rf /data/mysql3307/data/auto.cnf 
[root@radius01 ~]# nohup /usr/local/mysql3306/bin/mysqld_safe --datadir=/data/mysql3306/data --pid-file=/data/mysql3306/data/mysql.pid &
[root@radius01 ~]# nohup /usr/local/mysql3307/bin/mysqld_safe --datadir=/data/mysql3307/data --pid-file=/data/mysql3307/data/mysql.pid &  
[root@radius01 ~]# cat /data/mysql3306/data/auto.cnf
[auto]
server-uuid=f6a726d2-96fd-11e7-b0c8-aaafa07a2e23
[root@radius01 ~]# cat /data/mysql3307/data/auto.cnf 
[auto]
server-uuid=fc6ee68c-96fd-11e7-b0c8-aaafa07a2e23
-------------------------------------------------------------------------------------------------------------------------------------
 
數據同步測試：
在主庫里寫入新數據
[root@radius01 ~]# /usr/local/mysql3306/bin/mysql -p123456 -S /usr/local/mysql3306/var/mysql.sock
mysql> create database wangshibo;
mysql> use wangshibo;
mysql> create table tehui(
    -> id int not null primary key,
    -> name varchar(10));
mysql> insert into tehui values(1,"huanhuan");
mysql> insert into tehui values(11,"meimei");
mysql> select * from tehui;
+----+----------+
| id | name     |
+----+----------+
|  1 | huanhuan |
| 11 | meimei   |
+----+----------+
2 rows in set (0.00 sec)
 
在從庫查看是否已同步
[root@radius01 ~]# /usr/local/mysql3307/bin/mysql -p123456 -S /usr/local/mysql3307/var/mysql.sock
mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| test               |
| wangshibo          |
+--------------------+
5 rows in set (0.00 sec)
 
mysql> use wangshibo;
mysql> show tables;
+---------------------+
| Tables_in_wangshibo |
+---------------------+
| tehui               |
+---------------------+
1 row in set (0.00 sec)
 
mysql> select * from tehui;
+----+----------+
| id | name     |
+----+----------+
|  1 | huanhuan |
| 11 | meimei   |
+----+----------+
2 rows in set (0.00 sec)