RESET MASTER;
connect  slave,127.0.0.1,root,,,$SERVER_MYPORT_3;
change master 'abc1' to relay_log_file='';
ERROR HY000: Failed initializing relay log position: Could not find target log during relay log initialization
change master 'abc1' to relay_log_file='';
ERROR HY000: Failed initializing relay log position: Could not find target log during relay log initialization
disconnect slave;
connection default;