При change master на mysql slave  излиза следната грешка съпроводена с решение :) :

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mysql> stop slave;
Query OK, 0 rows affected, 1 warning (0.00 sec)

mysql> CHANGE MASTER TO MASTER_HOST='192.193.123.4', MASTER_USER='slaveuser', MASTER_PASSWORD='pass', MASTER_LOG_FILE='mysql-bin.000020', MASTER_LOG_POS=49869;
ERROR 1201 (HY000): Could not initialize master info structure; more error messages can be found in the MySQL error log

mysql> reset slave;
Query OK, 0 rows affected (0.00 sec)

mysql> CHANGE MASTER TO MASTER_HOST='192.193.123.4', MASTER_USER='slaveuser', MASTER_PASSWORD='pass', MASTER_LOG_FILE='mysql-bin.000020', MASTER_LOG_POS=49869;
Query OK, 0 rows affected (0.02 sec)

mysql> start slave;
Query OK, 0 rows affected (0.00 sec)