SQL Thread is not running
When relay log is corrupted , meaning the slave server is stopped unexpectedly
How to fix:
– run show slave , we’ll see the IO thread running but SQL thread is not working.
– check Relay_Log_File name , for example , mysqld_3308-relay-bin.000044
then we know that 44 is corrupted, so we’ll increase it
stop slave; change MASTER To Relay_Log_File='mysqld_3308-relay-bin.000045',Relay_Log_Pos=4; start slave;
SQL IO is not runnning
run show slave to check Master_Log_File value , then increase it to 1
Check : Master_Log_File mysql-bin.003591
stop slave; change MASTER To Master_Log_File='mysql-bin.003592',MASTER_LOG_POS=4; start slave;