IronPort - advanced configuration guide

Chapter 2 Configuring Routing and Delivery Features
Cisco IronPort Bounce Verification and the HAT
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AsyncOS also includes a HAT setting related to Cisco IronPort Bounce Verification for considering
whether untagged bounces are valid. The default setting is “No,” which means that untagged bounces
are considered invalid and the appliance either rejects the message or applies a customer header,
depending on the action selected on the Mail Policies > Bounce Verification page. If you select “Yes,”
the appliance considers untagged bounces to be valid and accepts them. This may be used in the
following scenario:
Suppose you have a user that wants to send email to a mailing list. However, the mailing list accepts
messages only from a fixed set of Envelope Senders. In such a case, tagged messages from your user will
not be accepted (as the tag changes regularly).
To help that user, follow these steps:
Step 1 Add the domain to which the user is trying to send mail to the Destination Controls table and disable
tagging for that domain. At this point, the user can send mail without problems.
Step 2 However, to properly support receiving bounces from that domain (since they will not be tagged) you
can create a sender group for that domain and enable the Consider Untagged Bounces to be Valid
parameter in an “Accept” mail flow policy:
Figure 2-12 The Consider Untagged Bounces to be Valid HAT Parameter
Working with Cisco IronPort Bounce Verification
When configuring Cisco IronPort Bounce Verification, follow these steps:
Step 1 Enter a tagging key (see Configuring Bounce Verification Address Tagging Keys, page 2-56).
Step 2 Edit the bounce verification settings (see Configuring Cisco IronPort Bounce Verification Settings,
page 2-56).
Step 3 Enable bounce verification via Destination Controls (see Working with Destination Controls,
page 2-46).
Cisco IronPort AsyncOS 7.6 for Email Advanced Configuration Guide
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