Limiting the Number of z/OS IPL Messages Displayed on CI

As part of the z/OS Load parameter specification, the initialization message suppression indicator (IMSI) can be chosen to control the suppression of messages and system prompts during initialization.

The IMSI character tells the system whether to perform the following actions during system initialization:

Display most informational messages
Prompt for system parameters
Prompt for the name of the master catalog

See the section Loading the System Software in z/OS MVS System Commands for a table that shows the possible values for the IMSI character. The values indicate all possible combinations of the actions that are listed.

Whenever possible, it is recommended that you suppress the display of informational messages to reduce the total number of messages at IPL time. If you plan for z/OS IPL automation do not use informational messages as automation action triggers. Choose only messages that cannot be suppressed, in addition to action or decision operator prompts.