FORWARD mapping table

The  mapping table provides functionality of pattern-based  forwarding (analogous to the way that the   mapping table provides pattern-based changes to non-routing addresses),  and the   mapping table  also provides a mechanism for source specific  forwarding. If a  mapping table exists, it is applied to each envelope To address. The probe of the  mapping table by default consists simply of the current envelope To  address: envelope-to But bits of the   MTA option and   MTA option control inclusion of  additional fields in the probe. Bit 4 (value 16) of the   MTA option controls including the    and    in the probe; bit 6 (value 64) of    controls including the current    in the probe; new in MS  6.3, enabling bit 2 (value 4) of the     MTA option causes any current  conversion tags on the message to be included  in a comma-separated list  clause in the probe. With these additional fields enabled, the probe has the form source-channel&#x7c;from-address&#x7c;destination-channel&#x7c;tag-list&#x7c;envelope-to New in MS 8.0, the   MTA option and    MTA option control,  respectively, the inclusion of MT-PRIORITY and expected message size,  and LDAP "spare" attribute values associated with the sender address, in the probe. Also new in MS 8.0 are new bits of the     MTA option controlling inclusion of the  initial form and intermediate form of the recipient address, and the authenticated sender address, in the  probe. With all these options enabled as well as the previously discussed options, the probe has the form: src-chan&#x7c;from-addr&#x7c;dst-chan&#x7c;auth-sender&#x7c;tag-list&#x7c;s1&#x7c;s2&#x7c;s3&#x7c;s4&#x7c;s5&#x7c;s6&#x7c;mtpriority&#x7c;expected-size&#x7c;initial-to&#x7c;inter-to&#x7c;envelope-to New in MS 8.0.2.2, LDAP "spare" attribute values associated with the recipient address can also be included in the probe. These appear after the sender spare attributes and are controlled by additional bits in the  MTA option.

Note that when the   is included in the probe, then the MTA options  , and (new in MS 6.3)   ,  and (new in MS 7.0)   ,  can be used to  select which form of the envelope From address is included.

If the probe matches a  mapping table entry pattern, the result  of the mapping is tested. The resulting string will replace the envelope To address if the entry template specifies a  ;  a   will discard the result of the mapping. See FORWARD mapping table flags for a list of  additional flags, and see Mapping tables  for general background and syntax of mapping tables. If no entries in the   mapping table match, or if no    mapping table exists,  then the MTA&#x27;s envelope To address processing proceeds to its next  stage.

The  mapping, if present, is consulted before any  forward database lookup. If a  mapping matches and has the flag  , then the result of the    mapping will be checked  against the forward database, if forward database use has been enabled  via the appropriate setting of. (Note that if channel specific forward database use has been specified, then the  source address and source channel will be prefixed to the result of the    mapping before looking up in the forward database.) If a  matching   mapping entry specifies , then the  result of the   mapping (and optional forward database lookup)  will be run through the MTA&#x27;s address rewriting process again. If a matching   mapping entry specifies , then no  further   mapping or database lookups will be performed during  that subsequent address rewriting (that resulting from the use of   ).

See also the    MTA option which may be used to specify the name of a domain-level LDAP attribute whose value names an MTA mapping table that functions, for addresses in the domain which match no specific user entry, similarly to the   mapping table. That is, it provides a domain-specific, more restrictive (applying only to addresses which have no explicit user entry), analogue of the  mapping table.

See also:
 * use_forward_database MTA Option
 * include_conversiontag MTA Option
 * include_mtpriority MTA Option
 * include_spares2 MTA Option
 * Aliases
 * Forward database
 * Sieve fileinto action
 * Alias file named parameters
 * viaaliasrequired Option
 * ldap_domain_attr_catchall_mapping MTA Option
 * Mapping tables
 * Forwarding mail