#此时查看从库的状态信息
slave@localhost[(none)]> show slave status \G
*************************** 1. row ***************************
Slave_IO_State:
Master_Host: 192.168.1.177
Master_User: repl
Master_Port: 3406
Connect_Retry: 60
Master_Log_File: inst3406bin.000001
Read_Master_Log_Pos: 4
Relay_Log_File: relay-bin.000001
Relay_Log_Pos: 4
Relay_Master_Log_File: inst3406bin.000001
Slave_IO_Running: No #IO线程没有运行
Slave_SQL_Running: No #SQL线程没有运行
......................
Master_Info_File: /data/inst3506/data3506/master.info
slave@localhost[(none)]> start slave; #启动slave
Query OK, 0 rows affected (0.01 sec)
#含义如下
START SLAVE with no thread_type options starts both of the slave threads. The I/O thread reads
events from the master server and stores them in the relay log. The SQL thread reads events from the
relay log and executes them.
#再次查看slave的状态
robin@localhost[(none)]> show slave status\G
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.1.177
Master_User: repl
Master_Port: 3406
Connect_Retry: 60
Master_Log_File: inst3406bin.000001
Read_Master_Log_Pos: 120
Relay_Log_File: relay-bin.000002
Relay_Log_Pos: 285
Relay_Master_Log_File: inst3406bin.000001
Slave_IO_Running: Yes #IO线程处于运行状态
Slave_SQL_Running: Yes #SQL线程处于运行状态
..............
Exec_Master_Log_Pos: 120
Relay_Log_Space: 452
............
Master_Server_Id: 3406
Master_UUID: 32f53a0a-63ef-11e4-93d9-8c89a5d108ae
Master_Info_File: /data/inst3506/data3506/master.info
SQL_Delay: 0
SQL_Remaining_Delay: NULL
Slave_SQL_Running_State: Slave has read all relay log; waiting for the slave I/O thread to update it #重要的提示信息
#可以看到从库上的2个线程，一个是用于I/O线程，用于连接到主库请求主库发送binlog，一个是用于执行SQL的SQL线程。
slave@localhost[(none)]> show processlist\G
*************************** 1. row ***************************
Id: 4
User: system user
Host:
db: NULL
Command: Connect
Time: 510993
State: Waiting for master to send event
Info: NULL
*************************** 2. row ***************************
Id: 5
User: system user
Host:
db: NULL
Command: Connect
Time: 333943
State: Slave has read all relay log; waiting for the slave I/O thread to update it
Info: NULL
5、验证同步情况