USERMAPPING configuration parameter (UNIX, Linux)

Use the USERMAPPING configuration parameter to set whether or not the database server accepts connections from mapped users.

default value
OFF = Only users that are registered in the HCL Informix® host computer OS with a login service can connect to the database server. Externally authenticated users without OS accounts on the Informix host computer cannot connect to database server resources.

BASIC = Users can connect to Informix without an OS account. A user without an OS account cannot perform privileged user operations on the database server, even if the user maps to a server administrator user or group ID.

ADMIN = Users can connect to Informix without an OS account. If a user has authenticated with the identity of a privileged user and is mapped to the proper server administrator group ID, the user can perform DBSA, DBSSO, or AAO work on the database server.

takes effect
After you edit your onconfig file and restart the database server.
When you reset the value dynamically in your onconfig file by running the onmode -wf command.
When you reset the value in memory by running the onmode -wm command.


Externally authenticated users without operating system (OS) accounts on the Informix host computer can access database server resources when USERMAPPING is turned on by setting the parameter with the BASIC or ADMIN value. The setting of BASIC or ADMIN also determines whether or not mapped users can be granted administrative privileges.

Important: Changing the USERMAPPING configuration parameter from OFF to ADMIN or BASIC is not the only step in setting up Informix for mapped users. To map users with the appropriate user properties, you must also use DDL statements such as CREATE USER and ALTER USER to register values in appropriate system tables of the SYSUSER database. Depending on the DDL statement used and the defined table mapping, the following tables will be updated or populated:

Copyright© 2018 HCL Technologies Limited