*spamfilter* Channel options

,, ,   ,  ,    Channel Options
The  ,   ,   ,    ,   , and      channel options  control whether spam/virus filter package processing is invoked by the MTA during message enqueue processing.

As of Messaging Server 7.0.5, the   utility  is also capable of invoking spam/virus filter packages,  "as if" it were an MTA channel. For such use,  is told a source channel as which to operate, and  then any    and     channel options for that channel specify what spam/virus filter package(s) to invoke.   The MTA supports the use of up to eight distinct spam/virus filtering packages, as configured via the     MTA options (with   ranging between   and  );  the set of options with the same number all configure one of the distinct packages. And the number in a    channel option correlates with which spam/virus filter package is to be invoked (or not invoked). (Note that the  options, and the   options without an explicit number, are deprecated synonyms for the   options. These deprecated forms are not allowed in a Unified Configuration.)

The    channel options not only trigger  spam/virus filter package processing, but do so with a particular "opt-in" value or values set, as some spam/virus filter packages (such as Brightmail) support different "choices" or "opt-in" values for what type of filtering will be performed (e.g.,   vs.  ). The MTA supports use of multiple, comma-separated "opt-in" values as an argument to an   channel option. Spam/virus filter package processing may also be triggered, with a specific "opt-in" value or values, via use of a per-user attribute (see the    and     MTA options) or a  per-domain attribute (see the      MTA options). When "opt-in" values from multiple sources apply for a message -- for instance, if an "opt-in" value is set via a channel option as well as via an attribute---the MTA will pass all the applicable "opt-in" values to the spam/virus filter package.

The  channel options enable spam/virus filter package processing based upon source channel; when such a channel option applies, the spam/virus filter package will be activated towards the start of the SMTP dialogue (MAIL FROM stage). (For even earlier spam/virus filter package activation, see Spamfilter early verdicts.) The  channel options enable spam/virus filter package processing based upon destination channel, which is determined for each recipient at the RCPT TO stage of the SMTP dialogue; so if a   channel option applies, that spam/virus filter package activation occurs at RCPT TO stage.

The   channel options can be used to disable, on a channel-specific basic, spam/virus filtering that would otherwise be performed. In particular, note that the    channel options override any user-level opt-in to spam/filter package processing (as for instance selected via an LDAP attribute named by an    MTA option),  and override any channel level opt-in (as for instance via a      channel option). For instance, one might use  on a    channel  to  disable spam/virus filtering (by spam/virus filter package number 1) for all messages coming in the   channel, overriding any spam/virus filter package use that might normally be triggered due to the destination channel or recipient address(es).

As of MS 8.0.1.3, the $+^ flag in the  mapping table can also be used to disable source channel spam filter optins. Also as of 8.0.1.3, the same $+^ flag in a recipient access mapping table can be used to disable any active spam filter optins at the current aliasing level. In either case the flag takes a comma separated list of spam filters to disable.

See also:
 * Spamfilter MTA options
 * ldap_optin1 MTA Option
 * ldap_optout1 MTA Option
 * ldap_domain_attr_optin1 MTA Option
 * imexpire invoking spamfilter packages
 * Spamfilter channel options
 * Channel options