Руководство Пользователя для Cisco Cisco Email Security Appliance X1050

For Routing queries, the value of MAILHOST cannot be an IP address; it must be a resolvable hostname. 
This usually requires the use of an Internal DNSconfig.

MAILHOST is optional for the routing query. MAILROUTINGADDRESS is mandatory if MAILHOST 
is not set.

Masquerading is a feature that rewrites the Envelope Sender (also known as the sender, or MAIL FROM) 
and the To:, From:, and/or CC: headers on email based on queries you construct. A typical example 
implementation of this feature is “Virtual Domains,” which allows you to host multiple domains from a 
single site. Another typical implementation is “hiding” your network infrastructure by “stripping” the 
subdomains from strings in email headers. 

(mailLocalAddress={a})

May not be applicable

a

a.Active Directory implementations can have multiple entries for the 

proxyAddresses

 attribute, but because

AD formats this attribute value as 

smtp:user@domain.com

, that data cannot be used for LDAP routing/alias

expansion. Each target address must be in a separate 

attribute:value

 pair. Microsoft Exchange

environments that are aware of each other within the infrastructure can usually route mail between each other
without involving a route back to the originating MTA. 

(mail={a})

(mailForwardingAddress={a})

(mailEquivalentAddress={a})

(mailRoutingAddress={a})

(otherMailbox={a})

(rfc822Mailbox={a})