autodns-dhcp_ddns(1) on Linux
The text 2d9cee3477db, as Debian 10 (Buster), Debian 9 (Stretch), Debian 8 (Jessie), Debian 7 (Wheezy), Debian 6.0 (Squeeze), Debian 5.0 (Lenny) shipped it. The page shows this text now.
the script that updates the dns and settles the dhcp stuff