Setting configuration parameters

The configuration file for the HCL® Informix® server is identified by the $ONCONFIG environment variable, but if you have not set the $ONCONFIG environment variable, the name used is onconfig. Even if you do not plan to use multiple servers, it is recommended that you use a file named onconfig.server_name.

About this task

If you selected to create a demonstration database server or customized the default configuration file while running the installation application, manual setup of the configuration parameters is not required for a functioning Informix® instance. However, all instances created without using the default configuration file in the installation application require further action to set values for at least some configuration parameters.

An Informix® installation includes a default configuration file at $INFORMIXDIR/etc/onconfig.std. This file has initial values for many of the configuration parameters. You can use onconfig.std as a template configuration file that you can copy and customize to how you will use the product and to the host environment.

The command-line genoncfg utility provides an alternate way to set the configuration parameters of an Informix® instance. With this feature, you set a short list of parameters in an input file, from which the utility then generates an Informix® configuration file that is optimized for both your anticipated usage and your host environment. For this method, you are not required to copy and modify an onconfig file as described in the following procedure.

For information about why to modify the default configuration parameters, see HCL® Informix® Administrator's Guide documentation about configuring the database server. The HCL® Informix® Administrator's Reference provides detailed information about all the configuration parameters and the genoncfg utility.

Important: Do not modify or delete onconfig.std, which is a template and not a functional configuration.

To prepare an Informix® configuration file:

Procedure

  1. Copy the onconfig.std template file.
  2. Modify the copy of the template file.
    The default value for the DUMPDIR parameter is $INFORMIXDIR/tmp. If you change this value in your configuration file, make sure that you specify a valid directory on your computer.
  3. Set the ONCONFIG environment variable to the name of your customized configuration file.

Results

If you omit a parameter value in your copy of the configuration file, the database server either uses default values from the onconfig.std template file or calculates values based on other parameter values.