"Unable to create listener" errors are returned when some other service is utilizing the Broker's UDP or TCP ports; this may be a previously started instance of the Broker, or any other process. If you receive "Unable to create listener" errors, take the following action:
ps -ef | grep oplrqb | grep -v grep (Unix) or the Task Manager (Windows) to search for a running Broker process.
If you find one, terminate it.
You cannot run two Broker instances on one machine.
netstat -a | grep 60001 from DOS or a UNIX terminal to check whether another service is using UDP Port 60001.
If so, try to reassign that service, or start the Broker before the other service.
60001 is free, use netstat -a | grep <port-number> to check the status of the Broker's Listen and PortLow TCP ports.
These ports both default to 5000.
However, you may want to verify your settings.
Take the following action: oplrqb.ini file.
You will find this file in the /bin sub-directory of your Multi-Tier server components installation.
[Protocol TCP] section.
PortLow and Listen.
netstat output.