之前在自己的虚拟机上一台服务器安装了两个mysql实例，现在利用这两个实例来尝试配置mysql的主从关系。

将3306端口的实例设为主库，3307端口的实例设为从库。

步骤：

1、修改主库和从库的配置文件my.cnf：

主库：[root@single1 mysql]# cat my.cnf
[mysqld]
basedir=/usr/local/mysql
datadir=/usr/local/mysql/data
socket=/usr/local/mysql/mysql.sock
port=3306
user=mysql
server-id=1                          
log-bin=mysql-bin
binlog_ignore_db=mysql
character_set_server=utf8

# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0
innodb_data_file_path=ibdata1:12M:autoextend
innodb_log_files_in_group=2
innodb_log_file_size=50331648

[mysqld_safe]
log-error=/usr/local/mysql/single1.log

[mysql]
socket = /usr/local/mysql/mysql.sock
default-character-set=utf8

从库：

[root@single1 mysql3307]# cat my.cnf
[mysqld]
basedir=/usr/local/mysql3307
datadir=/usr/local/mysql3307/data
socket=/usr/local/mysql3307/mysql.sock
port=3307
user=mysql
server-id=2                          
log-bin=mysql-bin
binlog_ignore_db=mysql
character_set_server=utf8

[mysqld_safe]
log-error=/usr/local/mysql3307/single1.log

[mysql]
socket = /usr/local/mysql3307/mysql.sock
default-character-set=utf8

注意：

主库和从库的server-id是必须不一样的，默认为1。

log-bin参数表示启用二进制日志。

binlog_ignore_db参数表示忽略mysql数据库的日志

2、重启mysql实例：

    service mysql  restart

    service  mysql3307 restart

3、创建用户用于同步用：

从库：

mysql -S /usr/local/mysql3307/mysql.sock -P 3307 -uroot -p   
mysql> create user backup;
Query OK, 0 rows affected (0.01 sec)

mysql> set password for backup=password('backup');
Query OK, 0 rows affected (0.00 sec)

主库：

mysql -S /usr/local/mysql/mysql.sock -P 3306 -uroot -p

mysql> GRANT REPLICATION SLAVE,RELOAD,SUPER ON *.*  to backup@'192.168.2.151' identified by 'backup';
Query OK, 0 rows affected (0.05 sec)to backup@'192.168.2.151' identified by 'backup';
注：192.168.2.151这个IP地址是从库的IP地址。
    REPLICATION CLIENT权限，用于查看slave进程的状态
    REPLICATION SLAVE权限，用于复制进程
    SUPER权限，用于停止和开启slave进程
    RELOAD权限，用于reset slave;

4、查看主库的状态：

主库：

mysql -S /usr/local/mysql/mysql.sock -P 3306 -uroot -p

mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000001 |      120 |              | mysql            |                   |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.02 sec)

5、配置从库：

从库：

mysql -S /usr/local/mysql3307/mysql.sock -P 3307 -ubackup -p

change master to master_host='localhost', master_user='backup', master_password='root', master_log_file='mysql-bin.000001', master_log_pos=120, master_port=3306; 

#一定要指定相应的端口号，不然在查看状态时会出错。master_log_file和master_log_pos的值由主库的状态查看得出。
start slave;
show slave status\G;

注：Slave_IO及Slave_SQL进程必须正常运行，即YES状态，否则都是错误的状态(如：其中一个NO均属错误)。

6、测试:

主库：

create database test2;

use test2;

create table t as select * from mysql.user;

备库：

show database;

use test2;

select count(1) from t;

到此，mysql主从配置结束