Before creating a database server, you must define the service of the database server in the /etc/services file or its NIS equivalent (for more information, see Services, routing, passwords, groups, and hosts).
The services entry for the database server has the following syntax:
servername_serverhostname informix_port/tcp # comment
The first column is the Informix® database server service name. The second column starts with the Informix service port number.