MySQL主从同步状态

     因为mysql的slave报错，导致slave落后master很远。找资料查看同步状态。

引用

mysql> show slave status\G

*************************** 1. row ***************************

               Slave_IO_State: Waiting for master to send event

                  Master_Host: 192.168.0.103

                  Master_User: root

                  Master_Port: 3306

                Connect_Retry: 10

              Master_Log_File: masterlog.000298

          Read_Master_Log_Pos: 780437928

               Relay_Log_File: db-relay-bin.000246

                Relay_Log_Pos: 589923335

        Relay_Master_Log_File: masterlog.000298

             Slave_IO_Running: Yes

            Slave_SQL_Running: Yes

              Replicate_Do_DB: byread

          Replicate_Ignore_DB:

           Replicate_Do_Table:

       Replicate_Ignore_Table:

      Replicate_Wild_Do_Table:

  Replicate_Wild_Ignore_Table:

                   Last_Errno: 0

                   Last_Error:

                 Skip_Counter: 0

          Exec_Master_Log_Pos: 780437928

              Relay_Log_Space: 793806494

              Until_Condition: None

               Until_Log_File:

                Until_Log_Pos: 0

           Master_SSL_Allowed: No

           Master_SSL_CA_File:

           Master_SSL_CA_Path:

              Master_SSL_Cert:

            Master_SSL_Cipher:

               Master_SSL_Key:

        Seconds_Behind_Master: 0

Master_SSL_Verify_Server_Cert: No

                Last_IO_Errno: 0

                Last_IO_Error:

               Last_SQL_Errno: 0

               Last_SQL_Error:

1 row in set (0.00 sec)

如果下面一个为NO，表明同步停止。

引用

If either of these is NO, like this, then replication is stopped:

Slave_IO_Running: No

Slave_SQL_Running: No

以下两项会告诉你什么出错。

引用

The Last_Errno and Last_Error might give you a clue as to what went wrong.

[url]

http://homepage.mac.com/kelleherk/iblog/C711669388/E20070717105144/index.html

[/url]

同步主库文件和位置

引用

Master_Log_File: masterlog.000298

Read_Master_Log_Pos: 780437928

从库执行到的文件位置

引用

Relay_Master_Log_File: masterlog.000298

Exec_Master_Log_Pos: 780437928

当主库和从库对应一致时表明同步正常。