Tcprules

From Qmail Info Wiki

tcprules is part of the ucspi-tcp package. Its job is to create cdb files which are used by tcpserver (and can also be used by sslerver) to control which IP addresses are and are not allowed to connect, as well as any environment variables which need to be set when a connection is accepted.

The program is normally run as part of an automated process. I use an /etc/tcp directory which contains all of my text files and their cdb files, along with a Makefile which allows me to make updates to the text files and then simply type "make" to rebuild the cdb files as needed.

Because the files it creates are cdb files, there is no need to restart the tcpserver processses which uses these files when you make a change.