Cisco Cisco Email Security Appliance C170 Guia Do Utilizador
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Cisco AsyncOS 8.0.2 for Email User Guide
Chapter 19 Validating Recipients Using an SMTP Server
Bypassing SMTP Call-Ahead Validation for Certain Users or Groups
•
If the LDAP routing query returns a single hostname with a port, the SMTP route is used, but the
port returned by the LDAP query is used over any ports specified in SMTP routes. If the SMTP
routes only lists the destination host as the hostname, a DNS lookup is performed to obtain the IP
address of the SMTP server.
port returned by the LDAP query is used over any ports specified in SMTP routes. If the SMTP
routes only lists the destination host as the hostname, a DNS lookup is performed to obtain the IP
address of the SMTP server.
•
If the LDAP routing query returns multiple hosts with or without ports, SMTP routes are applied,
but the ports returned by the LDAP routing query are used over those present in SMTP routes. If the
SMTP routes only lists the destination host as the hostname, a DNS lookup is performed to obtain
the IP address of the SMTP server.
but the ports returned by the LDAP routing query are used over those present in SMTP routes. If the
SMTP routes only lists the destination host as the hostname, a DNS lookup is performed to obtain
the IP address of the SMTP server.
Bypassing SMTP Call-Ahead Validation for Certain Users or
Groups
Groups
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.
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.
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.
when you add or edit the RAT entry.