How to fix the Oracle error CLSGN-00209: Listen for DNS requests failed. IP address string port number is in use.?

In this post, you’ll learn more about the Oracle ErrorCLSGN-00209: Listen for DNS requests failed. IP address string port number is in use. with the details on why you receive this error and the possible solution to fix it.

Oracle Error Description

CLSGN-00209: Listen for DNS requests failed. IP address string port number is in use.

Reason for the Error CLSGN-00209: Listen for DNS requests failed. IP address string port number is in use.

Listening for requests from the DNS server(s) failed because another process is using the address.

How to fix the Error CLSGN-00209: Listen for DNS requests failed. IP address string port number is in use. ?

You can fix this error in Oracle by following the below steps

If another GNS instance is running, this error is expected. Otherwise, terminate the process using the address or start GNS on another node.