select @@global.report_port; @@global.report_port DEFAULT_MASTER_PORT select @@session.report_port; ERROR HY000: Variable 'report_port' is a GLOBAL variable show global variables like 'report_port'; Variable_name Value report_port DEFAULT_MASTER_PORT show session variables like 'report_port'; Variable_name Value report_port DEFAULT_MASTER_PORT select * from information_schema.global_variables where variable_name='report_port'; VARIABLE_NAME VARIABLE_VALUE REPORT_PORT DEFAULT_MASTER_PORT select * from information_schema.session_variables where variable_name='report_port'; VARIABLE_NAME VARIABLE_VALUE REPORT_PORT DEFAULT_MASTER_PORT set global report_port=1; ERROR HY000: Variable 'report_port' is a read only variable set session report_port=1; ERROR HY000: Variable 'report_port' is a read only variable