Administrator's Guide - Kerio Software Archive

Chapter 16 Antispam control of the SMTP serverOnly log this to the Security logAll messages of this type will be logged to the Security log. Messages with invalid Caller IDwill be delivered to the addressee.Block the messageMessage including invalid Caller ID will be blocked on SMTP level. Senders are informedthat their message cannot be delivered.Add this value to the message’s spam scoreThe value set here will be added to message’s total score (see section 16.1).In case of the Caller ID method, it is recommended to use value from 1 to 3 points.Apply this policy also to testing Caller ID recordsCurrently the Caller ID technology has not been widely adopted. Therefore, it is oftenused by domains in testing mode only (the XML script’s header in the corresponding DNSrecord includes the testing flag). For this reason, many domains use it only in a testingmode (headers of XML scripts in DNS records contain the testing item). Therefore, itis recommended to enable this option (otherwise, Caller ID will not function for mostdomains).Warning: With this option enabled, do not set the Block the message option for messageswith an invalid Caller ID.Don’t check Caller ID from...Use this option especially for specifying backup servers. If a message is sent througha backup server, the IP address of the server does not match the ones allowed for thedomain. Therefore the messages from these addresses should not be checked.This is why messages sent from these addresses should not be checked.Check my email policy DNS recordsClick the link to Kerio Technologies web pages where the email policy DNS record fora domain can be checked.Note: For detailed instructions on proper configuration of DNS entry settings for Caller ID, seethe official Microsoft web pages.SPFSPF is an open source equivalent to Caller ID developed by Microsoft. Both technologies canbe used simultaneously in Kerio MailServer.In the SPF tab, the following options are available:Enable SPF check of every incoming messageEnable/disable use of SPF.On the Relay Control tab in the SMTP server section, it is possible to define a group oftrustworthy IP addresses. SPF check will not be applied to messages sent from trustworthyIP addresses (for details, see chapter 15.2).186