This configuration setting control which domains the system can send trackback pings or TrackBack auto-discovery requests to if enabled in OutboundTrackbackLimit setting.

This option is the configuration file counterpart to the Outbound TrackBack Control settings found on System Overview » Preferences » Feedback.

Examples

Allow TrackBack traffic only to example.com and any of its subdomains:

OutboundTrackbackDomains example.com

Allow TrackBack traffic only to intranet.example.com:

OutboundTrackbackDomains intranet.example.com

Allows TrackBack traffic to three different domains

OutboundTrackbackDomains example_one.com
OutboundTrackbackDomains example_two.com
OutboundTrackbackDomains example_three.com

This can also be done on a single line:

OutboundTrackbackDomains example_one.com example_two.com example_three.com

Don't forget, OutboundTrackBackDomains must always be accompanied by the following in the config file to be enabled:

OutboundTrackbackLimit  selected