knockd(1) on Linux
The text fb724bd07308, as Debian 11 (Bullseye), Debian 10 (Buster), Debian 9 (Stretch) shipped it.
port-knock server
Flags it lists
-
--config -
--daemon -
--debug -
--help -
--interface -
--lookup -
--verbose -
--version -
-D -
-V -
-c -
-d -
-h -
-i -
-l -
-v