Building and Controlling AOF Rules › Execution of Enabled Rules › How Multiple Rules Execute in Response to a Single Event

How Multiple Rules Execute in Response to a Single Event

You can write any number of rules that respond to a single event. Except for time rules with exactly matching event criteria, rules execute in a predictable order, as shown:

1. Rules with the most specific event criteria are tested first.

   For example, message rules with most specific to least specific event specifiers are tested in this order:

   • IST020I (Seven significant characters-most specific)
   • IST*I (Four significant characters-less specific)
   • IST* (Three significant characters-least specific)
2. Event specifiers containing the same number of significant characters are tested in the order of longest prefix length.

   For example, if three event specifiers all contain six significant characters, they are tested in this order:

   • IST02*I (Five-character prefix)
   • IST0*0I (Four-character prefix)
   • IST*20I (Three-character prefix)
3. Rules containing identical event specifiers are tested in unpredictable order. If you want the rules to execute in a particular order, then combine them into a single rule.

   However, do not combine unrelated rules because doing so makes applications difficult to manage.

Note: If you have to continually rely on the above executing order, you may be developing an ineffective application. You should incorporate the logic of the multiple rules into one rule.