How to Change DB Control Http Port.

1)Stop the dbconsole.

bash-3.00$ emctl stop dbconsole
Oracle Enterprise Manager 10g Database Control Release 10.2.0.1.0
Copyright (c) 1996, 2005 Oracle Corporation. All rights reserved.
http://neptune:5500/em/console/aboutApplication
Stopping Oracle Enterprise Manager 10g Database Control ...
... Stopped.

2)Take a backup of files:

$ORACLE_HOME/host_sid/sysman/config/emoms.properties
$ORACLE_HOME/host_sid/sysman/config/emd.properties
$ORACLE_HOME/oc4j/j2ee/OC4J_DBConsole_host_sid/config/http-web-site.xml

3)Edit these three files. Suppose My hostname is neptune and sid is data1 and I like to change it to port 510. To do this following is the procedures. You can either edit files directly or you can use command line utility to change the port.

Editing directly inside files
In /oracle/app/oracle/product/10.2.0/db_1/neptune_data1/sysman/config/emoms.properties

oracle.sysman.emSDK.svlt.ConsoleServerPort=5510
oracle.sysman.emSDK.svlt.ConsoleServerHTTPSPort=5510

In /oracle/app/oracle/product/10.2.0/db_1/neptune_data1/sysman/config/emd.properties

REPOSITORY_URL=http://host.domain:5510/em/upload/
emdWalletSrcUrl=http://host.domain:5510/em/wallets/emd

In /oracle/app/oracle/product/10.2.0/db_1/oc4j/j2ee/OC4J_DBConsole_neptune_data1/config/http-web-site.xml

<web-site port="5510" ...>

Command line Options to change DB Control Http Port
To change the Oracle Enterprise Management Agent HTTP port,
$ emca -reconfig ports -AGENT_PORT 1851

To change the Oracle Enterprise Manager Database Control ports,
$ emca -reconfig ports -DBCONTROL_HTTP_PORT 5510

To change the Oracle Enterprise Manager RMI_PORT port,
$ emca -reconfig ports -RMI_PORT 5520

To change the Oracle Enterprise Manager JMS_PORT port,
$ emca -reconfig ports -JMS_PORT 5521

You can change all these by single command like,
$ emca -reconfig ports -DBCONTROL_HTTP_PORT 5510 -AGENT_PORT 1851 -RMI_PORT 5520

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