The Oracle Management Agent uses a predefined port number to receive requests from the Management Service. This port number is defined by default when you install the Agent on a managed host. If you later need to modify this port, you can use the following procedure.
1. stop agent
<agent_home>/agent_inst/bin/emctl stop agent
2. backup emd.properties under <agent_home>/agent_inst/sysman/config/
3. vi emd.properties
4. Change the port number in EMD_URL property
For example:
EMD_URL=http://managed_host1.acme.com:1830/emd/main
5. Save the changes
6. Start Oracle Management Agent
<agent_home>/agent_inst/bin/emctl start agent