OpenBSD Journal

Quick Links from O'ReillyNet

Contributed by jose on from the roundup-of-random-stuff dept.

A few quick links for everyone.
  • Some months ago we talked about the Top Five Open Source Packages for SysAdmins , and the number one entry was missing. "Obviously it's OpenBSD!" Well, the number one tool has been named finally, and it's cfengine. This is available in ports, by the way.
  • Sometimes you have to traverse a firewall to get to a server. One way to do this is via "reverse telnet", typically done using netcat (nc, it's in the base install). This O'ReillyNet piece explains how to do this. A neat trick indeed.
  • A very recent O'ReillyNet article covers Privacy and Anonymity in Email . Many of these packages should work on OpenBSD.
Lots of useful stuff, give them a read.

(Comments are closed)

  1. By Anonymous Coward () on


  2. By S. Ramazani () on

    Why not use a SSH tunnel through the firewall to securely transfer files over the network ?

    1. By Krunch () on

      Why not use a cryptcat tunnel over a SSH tunnel over a HTTP(S) tunnel ?

    2. By Anonymous Coward () on

      Too easy and too secure.

    3. By rabbit () on

      Using netcat to transfer files is a bit useless indeed.
      But netcat is a valuable tool for debugging problems: you can use it to communiate with lots of services on the lowest level. You can also use telnet for that purpose, of course, but telnet doesn't do udp ;)

    4. By Tom Buskey () on

      Say scp doesn't work....

      ssh remote -L xx:
      remote% nc -lvp xx > file

      local% nc -v -w 2 xx file

      On C (connect from | to ):
      nc -v -w 2 $a | nc -v -w2 $b

      1. By Tom Buskey () on

        A -- C -- B
        On C connect to A and B:
        ssh A -L $a:$a
        ssh B -L $b:$b
        On A (from): nc -lvnp $a file
        On C (connect from | to ):
        nc -v -w 2 $a | nc -v -w2 $b

      2. By RC () on

        First off, SCP works almost every place SSH works.

        Second, if you have SSH working, why not just do the following:

        ssh user@host.domain "cat FileName" > LocalFile

        No need for anything but SSH (and cat).

  3. By Xenotrope () on

    "For a freshly installed computer, setting up a ftp server or, worse, meddling with rcp or scp protocols may be nauseating."

    Yes, it's so nauseating how scp is in the base install and requires no configuration just to work whatsoever. It's clear this author didn't have OpenBSD in mind. Keep that perspective when reading it and you should be OK.

    In other words, netcat is a neat little hack that can come in handy, but serious tools are *already* in place where serious users will want them.

  4. By Anonymous Coward () on

    ===> cfengine-1.4.12 is marked as broken: this version of cfengine has security problems.
    ===> Cleaning for cfengine-1.4.12

    oooops :) (-current)

  5. By Anonymous Coward () on

    I remember similar article concerning connection to the office using ssh. However it was written for FreBSD, but it works perfectly with OpenBSD. "Your Own Private SSH Session to Your Office" is written by Scott Nolde on


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