rinetd(8) — rinetd — Debian unstable — Debian Manpages
https://manpages.debian.org/unstable/rinetd/rinetd.8.en.html
rinetd redirects TCP or UDP connections from one IP address and port to another. rinetd is a single-process server which handles any number of connections to the address/port pairs specified in the file /etc/rinetd.conf.