Misc checks
Configuration directives
Following directives are defined for all modules listed below.
Syntax:
fail_action ignore
fail_action reject
fail_action quarantine
Default: quarantine
Action to take when check fails. See Check actions for details.
Syntax: debug boolean
Default: global directive value
Log both sucessfull and unsucessfull check executions instead of just unsucessfull.
require_mx_record
Check that domain in MAIL FROM command does have a MX record and none of them are "null" (contain a single dot as the host).
By default, quarantines messages coming from servers missing MX records, use 'fail_action' directive to change that.
require_matching_rdns
Check that source server IP does have a PTR record point to the domain specified in EHLO/HELO command.
By default, quarantines messages coming from servers with mismatched or missing PTR record, use 'fail_action' directive to change that.
require_tls
Check that the source server is connected via TLS; either directly, or by using the STARTTLS command.
By default, rejects messages coming from unencrypted servers. Use the 'fail_action' directive to change that.