Specify the desired port in the /server-root/plugins/snmp/magt/CONFIG file .
Run the start script as follows:
cd /server-root/proxy-admserv
./start -shell /server-root/plugins/snmp/magt/magt
/server-root/plugins/snmp/magt/CONFIG
/server-root/plugins/snmp/magt/INIT
The master agent will then start on the desired port. The user interface will be able to detect that the master agent is running.