STOP SLAVE FOR CHANNEL '';
SET GLOBAL master_info_repository = 'TABLE';

CHANGE MASTER TO master_host='127.0.0.1', master_port=12345, master_user='msandbox', master_password='msandbox', master_auto_position=1 FOR CHANNEL 'masterchan1';  

-- CHANGE MASTER TO master_host='127.0.0.1', master_port=12346, master_user='msandbox', master_password='msandbox', master_auto_position=1 FOR CHANNEL 'masterchan2';  

START SLAVE for channel 'masterchan1';
-- START SLAVE for channel 'masterchan2';

