Cisco Cisco Email Security Appliance C170 Guia Do Utilizador

When the Envelope Recipient (also known as the Envelope To, or 

RCPT TO

) of an 

email accepted by a listener matches an alias as defined in an alias table, the 
Envelope Recipient address of the email will be rewritten. 

A listener checks the alias table and modifies the recipients after checking the 
RAT and before message filters. Refer to “Understanding the Email Pipeline” in 
the Cisco IronPort AsyncOS for Email Configuration Guide. 

The Alias Table functionality actually rewrites the Envelope Recipient of the 
email. This is different than the 

smtproutes

 command (see 

), which does not rewrite the Envelope Recipient of the email, 

but instead simply reroutes the email to specified domains. 

Alias tables are defined in sections as follows: each section is headed by a domain 
context, which is a list of domains that the section is relevant to, followed by a list 
of maps. 

A domain context is a list of one or more domains or partial domains, separated 
by commas and enclosed in square brackets ('

[

' and '

]

'). A domain is a string 

containing letters, digits hyphens, and periods as defined in RFC 1035, section 
2.3.1., “Preferred name syntax.” A partial domain, such as 

.example.com

 is a 

domain that begins with a period. All domains that end with a substring matching 
the partial domain are considered a match. For example, the domain context 

.example.com

 would match 

mars.example.com

 and 

venus.example.com

. Below 

the domain context is a list of maps, which are aliases followed by a list of 
recipients. A map is constructed as follows:

a list of one or more aliases to 
match 

the colon 
character (“

:

”)

a list of one or more 
recipient addresses or 
aliases