IronPort - advanced configuration guide

Chapter 6 Using Message Filters to Enforce Email Policies
Random Rule
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}
When working with headers, remember that the current value of the header includes changes made
during processing (such as with filter actions that add, remove, or modify message headings). See
Message Header Rules and Evaluation, page 6-4 for more information.
The random rule generates a random number from zero to N-1, where N is the integer value supplied in
parenthesis after the rule. Like the header() rule, this rule may be used in a comparison, or may be used
alone in a “unary” form. The rule evaluates to true in the unary form if the random number generated
is non-zero. For example, both of the following filters are effectively equal, choosing Virtual Gateway
address A half the time, and Virtual Gateway address B the other half of the time:
load_balance_a:
strip-header('X-DeleteMe');
if (random(10) < 5) {
} else {
}
load_balance_b:
alt-src-host('interface_a');
alt-src-host('interface_b');
if (random(2)) {
} else {
}
alt-src-host('interface_a');
alt-src-host('interface_b');
Cisco IronPort AsyncOS 7.6 for Email Advanced Configuration Guide
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