DSNL310I THE ALIAS keyword keyword-value IS ALREADY IN USE.

Explanation

The port number specified for the PORT or SECPORT keyword in the MODIFY DDF command is already in use for the location, or for a different alias.
keyword
PORT or SECPORT
keyword-value
The value specified for the PORT or SECPORT keyword.

System action

The command is not processed.

User response

Use the output from the DISPLAY DDF command to see the ports that are defined for each alias and location name.