To help you control the amount of information you receive when monitoring the network, VTAM® allows some messages to be suppressed. Messages are divided into the following categories based on suppression level (in order, from the lowest suppression level to the highest):

1. Informational
2. Warning
3. Normal
4. Serious
5. Insuppressible

The categories to be suppressed can be specified, either with the SUPP start option or with the MODIFY SUPP command. By specifying one category, VTAM suppresses all messages in that category and all messages in lower categories. For example, if the operator issues MODIFY SUPP=NORM or if you code SUPP=NORM in the start options, all messages within the normal category and those below it, warning and informational, are suppressed.

The MODIFY SUPP command changes only the categories of messages that are suppressed, not the suppression level of messages. You can change the suppression level of a message by using USS facilities.

For information about the suppression level of each VTAM message, see z/OS Communications Server: SNA Messages.