Slave_IO_Running and Slave_SQL_Running is Yes but replication is not working

Question

I have setup a Master/Slave replicatio in two different servers with the exact same charachterisits. The MySQL version is 5.5 and the Slave connects to the Master through a VPN connection.

I have confiemd the replicatino is working, when I create a new database on the Master I can see the database exist in Slave. The problem is when I was doing some failure scenarios and shutdown the VPN, the replicaotin status on the Master didn't show any errors :

mysql> show slave status;

*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 10.0.0.2
                  Master_User: replication
                  Master_Port: 3306
                Connect_Retry: 60
              Master_Log_File: mysql-bin.000001
          Read_Master_Log_Pos: 52360
               Relay_Log_File: mysql-relay-log.000004
                Relay_Log_Pos: 441
        Relay_Master_Log_File: mysql-bin.000001
             Slave_IO_Running: Yes
            Slave_SQL_Running: Yes
              Replicate_Do_DB: 
          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: 52360
              Relay_Log_Space: 597
              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: 
  Replicate_Ignore_Server_Ids: 
             Master_Server_Id: 1
"""

As fars as I know if the Slave_IO_Running and Slave_SQL_Running is Yes this is an indication that the replication is working but this is not possible as there is no network connectivity between servers..

If I restart mysql in the slave then I will see a connection error and the replication status will be accurate, If I re-enable VPN without restarting the mysql on Slave it seems the replication will continue to work as normal if I create a new data base.

Can some one help ?

Answer 1

Maybe you should take a look at this replication option http://dev.mysql.com/doc/refman/5.5/en/replication-options-slave.html#option_mysqld_slave-net-timeout