Farsight Passive DNS project


See the ISC Passive DNS Architecture white paper for the full technical details.

The slide deck from the original August 2010 Passive DNS Hardening presentation also may be of interest. (Note that a few slides may be out of date.)

Sensor installation

See the step by step guide to set up a passive DNS sensor for the Farsight Passive DNS project.

Passive DNS deployment options

Most sensor operators install the sensor directly on the recursive DNS server being monitored. The nameserver implementation does not matter since the sensor captures DNS packets from the server's network interface. The sensor can also be installed on a network monitoring server with access to a network tap of the server's DNS traffic. For installation details, see Passive DNS Sensor.


See the Privacy Considerations for ISC Passive DNS white paper for details about privacy and passive DNS replication.

Other pages

Passive DNS Sensor

Passive DNS Sensor FAQ