How to find OPMN Port Number in an Oracle AS instance?

Way 1:

From $ORACLE_HOME/install/portlist.ini

Way 2:

From $ORACLE_HOME/opmn/conf/opmn.xml

Way 3:

Issue the following command in Oracle AS 10.1.3 or higher

$ opmnctl status –port

It will display output like ':6007' and the last 4 digit numbers represent the OPMN port number.