The Sysadmin’s Daily Grind: Portfwd

Charly's Column

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Incoming TCP connections do not always end up where they are supposed to. A freely configurable redirector points digital debris in the direction of a new and better place.

Just a little while back we discussed Rinetd [1], a TCP redirector. Rinetd is lean, reliable, and easy to configure; on the downside, it lacks some advanced features. This month I’ll examine Portfwd, a tool that includes some of those features missing from Rinetd. Portfwd (Port Forwarding Daemon, [2]) takes the form of a 116K tarball, which you can build and install in the normal way: ./configure; make; make install or almost. The all-important binary went into hiding in the src directory after I typed make install. A symlink (ln -s /usr/local/portfwd-0.27/src/portfwd/usr/bin/portfwd) took care of that.

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