Cisco Cisco Email Security Appliance C170 Guia Do Utilizador

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Cisco AsyncOS 9.1 for Email User Guide
 
Chapter 24      Configuring Routing and Delivery Features
  Directing Bounced Email
Related Topics
Handling Undeliverable Email
The AsyncOS operating system classifies undeliverable email, or “bounced messages,” into the 
following categories: 
You use the Bounce Profiles page on the Network menu in the GUI (or the 
bounceconfig
 command) to 
configure how AsyncOS handles hard and soft conversational bounces for each listener you create. You 
create bounce profiles and then apply profiles to each listener via the Network > Listeners page (or the 
listenerconfig
 command). You can also assign bounce profiles to specific messages using message 
filters. (See 
 for more information.)
Related Topics
Notes on Soft and Hard Bounces
For conversational soft bounces, a soft bounce event is defined as each time a recipient delivery 
temporarily fails. A single recipient may incur several soft bounce events. You use the Bounce 
Profiles page or the 
bounceconfig
 command to configure parameters for each soft bounce event. 
(See 
.)
“Conversational” bounces:
The remote domain bounces the message during the initial SMTP conversation. 
Soft bounces
A message that is temporarily undeliverable. For example, a user’s mailbox may be 
full. These messages can be retried at a later time. (e.g. An SMTP 4XX error code.) 
Hard bounces
A message that is permanently undeliverable. For example, the user no longer exists 
for that domain. These messages will not be retried. (e.g. An SMTP 5XX error code.) 
“Delayed” (or “Non-conversational”) bounces:
The remote domain accepts the message for delivery, only to bounce it at a later time. 
Soft bounces
A message that is temporarily undeliverable. For example, a user’s mailbox may be 
full. These messages can be retried at a later time. (e.g. An SMTP 4XX error code.) 
Hard bounces
A message that is permanently undeliverable. For example, the user no longer exists 
for that domain. These messages will not be retried. (e.g. An SMTP 5XX error code.)