Why do we get error when we run “opmnctl status” from “$INST_TOP/ ora/ 10.1.3/ opmn/ bin”

原文：http://onlineappsdba.com/index.php/2010/01/04/oracle-apps-r12-interviewreaders-question-opmnctl-status/

This post covers interview question (related to Oracle Apps R12) from one reader, If you have any question then email us or post it under comments section.
Q. Why do we get error when we run “opmnctl status” from “$INST_TOP/ ora/ 10.1.3/ opmn/ bin” where as $ADMIN_SCRIPTS_HOME/adopmnctl.sh works ?


For those who are new to Oracle Apps R12 or OPMN

ORACLE_HOME in application tier in Applications R12


Similar to Oracle Applications 11i, there are two ORACLE_HOMEs (but of version 10g) on application tier (three in total including database)
i) 10.1.3 (10g R3) for Web-Apps Tier (HTTP, OC4J – oacore, oafm, forms)
ii) 10.1.2 (10g R2) for forms & reports server

For technical differences between 11i & R12 click here

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What is opmnctl/adopmnctl ?

OPMN - Oracle Process Manager & Notification Server is component in Oracle Application Server (10g) to manage (start/stop/status) Application Server components (HTTP, OC4J)

adopmnctl - is wrapper around opmnctl to manage application server (10g R3 & 10g R3) in Oracle Applications (EBS) R12 . More information here

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What is INST_TOP in Oracle Apps ?


INST_TOP denotes new TOP in Apps R12 INSTANCE_HOME, more informationhere . INSTANCE_HOME
contains scripts, log and configuration files .

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Now back to question Why do we get error when we run “opmnctl status” from “$INST_TOP/ ora/ 10.1.3/ opmn/ bin” although we get output on running$ADMIN_SCRIPTS_HOME/ adopmnctl.sh

When you run opmnctl status from $INST_TOP/ora/10.1.3/opmn/bin you get error like below

$ ./opmnctl status
Error reading opmn.xml

Message:{$INST_TOP/ora/10.1.2/opmn/conf/opmn.xml (No such file or directory)}

Filename:{$INST_TOP/ora/10.1.2/opmn/conf/opmn.xml}

FileContent:{}

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This is because when you run “opmnctl status” from $INST_TOP/ora/10.1.3/opmn/bin, opmnctl executable picks up OPMN config file (opmn.xml) from $ORACLE_CONFIG_HOME/opmn/conf/opmn.xml
and $ORACLE_CONFIG_HOME by default is set to 10.1.2  ORACLE_HOME .

             It is still possible to display status using $INST_TOP/ora/10.1.3/opmn/bin/status but first set $ORACLE_CONFIG_HOME to10.1.3  (This can be done by executing 10.1.3 environment file i.e.$INST_TOP/ora/10.1.3/$SID_$hostname.env )

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Why don’t you get above error by running $ADMIN_SCRIPTS_HOME/ adopmnctl.sh ? adopmnctl.sh calls $INST_TOP/ora/10.1.3/$SID_$hostname.env and sets $ORACLE_HOME
and $ORACLE_CONFIG_HOME to 10.1.3 related executable and configuration files. adopmnctl.sh is correct script to manage services (start/stop/status) controlled by OPMN in R12.