因为20G以下，所以数据容量比较小，用mysqldump全库导出对业务影响不大，所以采用这种模式进行从库的搭建：

PS： master-data=1 ，record the Master_Log_File and Read_Master_Log_Pos:

1 backup the backup sql log
/usr/local/mysql/bin/mysqldump -uroot -p -S /usr/local/mysql/mysql.sock --default-character-set=utf8 --extended-insert=false --triggers -R --hex-blob --all-databases --master-data=1 --flush-logs >/tmp/create-master2-20140416.sql
2 scp the sql log to the slave from master
scp create-master2-20140409.sql 10.xx.3.x2:/tmp/
3 create the replication account in master db servers.
GRANT REPLICATION SLAVE ON *.* TO 'repl'@'%' IDENTIFIED BY 'xx@xx';
4 import the sql to slave
/usr/local/mysql/bin/mysql -uroot -p -S /usr/local/mysql/mysql.sock --default-character-set=utf8 < /tmp/
5 reset the replication slave status
find the master binlog position of slave from backup sql log file.
change master to master_user='repl', master_password='Plcc0805@replicationm2', master_host='10.xx.3.x1',master_port=3306, master_log_file='mysql-bin.008713',master_log_pos=120;

6 启动slave

start slave;

show slave status\G