Identify the Informix tcp port number Unix Database Servers Log in to your Unix database server as the Informix user. Ensure that the Informix environment has been correctly set. Execute this command: echo $INFORMIXSERVER Execute this command: more $INFORMIXDIR/etc/sqlhosts Look for the line that begins with your $INFORMIXSERVER value, and note the value that appears in the fourth column. This is your service name. Execute this command: more /etc/services Search the output for the line that beings with the service name you found in $INFORMIXDIR/etc/sqlhosts. Note the associated port number. Windows Database Servers Log in to your Windows database server. Open an MS-DOS command prompt. Run this command: regedit Drill down to HKEY_LOCAL_MACHINE\ SOFTWARE\ INFORMIX\ SQLHOSTS Look for the value passed to Service. Exit the Registry. Use Notepad to open the C:\Windows\System32\Drivers\etc\services or C:\WINNT\System32\Drivers\etc\services file. Look for the port number that corresponds to the service in the registry.