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Administration Guide

Third-party-based filters

Third-party-based filters

In addition to local and FortiGuard filters, FortiOS can leverage third-party sources, which are known as DNS-based blackhole lists (DNSBL) or Open Relay Behavior-modification Systems (ORBS). These are maintained lists of IP addresses that have been identified as associated with spamming.

The following example demonstrates how to configure a DNSBL. The config emailfilter dnsbl command is used to configure either DNSBL or ORBS.

To configure a DNSBL:
  1. Define the server to get the DNSBL list from:
    config emailfilter dnsbl
        edit 100
            set name "dnsbl"
            config entries
                edit 1
                    set status enable
                    set server <IP address or server name>
                    set action {reject | spam}
                next
            end
        next
    end
  2. Add the DNSBL list to an email filter profile:
    config emailfilter profile
        edit "email_filter_profile"
            set options spamrbl
            set spam-rbl-table 100
        next
    end

Third-party-based filters

In addition to local and FortiGuard filters, FortiOS can leverage third-party sources, which are known as DNS-based blackhole lists (DNSBL) or Open Relay Behavior-modification Systems (ORBS). These are maintained lists of IP addresses that have been identified as associated with spamming.

The following example demonstrates how to configure a DNSBL. The config emailfilter dnsbl command is used to configure either DNSBL or ORBS.

To configure a DNSBL:
  1. Define the server to get the DNSBL list from:
    config emailfilter dnsbl
        edit 100
            set name "dnsbl"
            config entries
                edit 1
                    set status enable
                    set server <IP address or server name>
                    set action {reject | spam}
                next
            end
        next
    end
  2. Add the DNSBL list to an email filter profile:
    config emailfilter profile
        edit "email_filter_profile"
            set options spamrbl
            set spam-rbl-table 100
        next
    end