Cisco Cisco Email Security Appliance C190 User Guide
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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
In this case, you can use the SMTP Call-Ahead field to create a routing query
that directs the SMTP call-ahead query to the servers listed in the
that directs the SMTP call-ahead query to the servers listed in the
callAhead
attribute. For example, you might create a routing query with the following
attributes:
attributes:
Figure 4-4
LDAP Routing Query Configured for SMTP Call-Ahead:
In this query, the
{d}
represents the domain part of the recipient address, and the
SMTP Call-Ahead Server Attribute returns the values for the call-ahead servers
and the port that should be used for the query: smtp2.mydomain.com,
smtp3.mydomain.com on port 9025.
and the port that should be used for the query: smtp2.mydomain.com,
smtp3.mydomain.com on port 9025.
Note
This example shows just one way to configure a query that enables you to use the
LDAP routing query to direct SMTP call-ahead queries to the correct SMTP
servers. You are not required to use the query string or specific LDAP attributes
described in this example.
LDAP routing query to direct SMTP call-ahead queries to the correct SMTP
servers. You are not required to use the query string or specific LDAP attributes
described in this example.
SMTP Call-Ahead Query Routing
When routing an SMTP call-ahead query, AsyncOS checks for information in the
following order:
following order: