Cisco Cisco Email Security Appliance C390 Guia Do Utilizador
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Cisco IronPort AsyncOS 7.5 for Email Advanced Configuration Guide
OL-25137-01
Chapter 4 Validating Recipients Using an SMTP Server
Bypassing SMTP Call-Ahead Validation
You may want to enable SMTP call-ahead validation on a listener but skip the
SMTP call-ahead validation for certain users or groups of users.
SMTP call-ahead validation for certain users or groups of users.
You may want to skip SMTP call-ahead validation for recipients for whom mail
should not be delayed during SMTP call-ahead queries. For example, you could
add a RAT entry for a customer service alias that you know is valid and will likely
need immediate attention.
should not be delayed during SMTP call-ahead queries. For example, you could
add a RAT entry for a customer service alias that you know is valid and will likely
need immediate attention.
To configure bypassing SMTP call-ahead validation via the GUI, select Bypass
SMTP Call-Ahead when you add or edit the RAT entry.
SMTP Call-Ahead when you add or edit the RAT entry.
Figure 4-6
Bypassing SMTP Call-Ahead: