Home > Linux > Webmin and TCP wrappers

Webmin and TCP wrappers

Reverend, reverend, is this a conspiracy?
Crucified for no things, an image beneath me
(Pantera – Cemetery Gates)

Eveyone knows what Webmin is… And Usermin. And Virtualmin. Those pesky anoying admin interfaces for people that don’t know shit about Unix administration. Those stuff should be forbidden by law on servers. But… there’s always someone who forces you to have webmin.

So, the other day, I got a request to limit access to set up Webmin from few FQDNs. Offcourse, ipfilter is out of the question, because you can’t have FQDN in your rules. iptables on Linux are also out, because they work on layer 3, and FQDNs are translated to IP addresses when you load your ruleset. So if for whatever reason (DynDNS being the obvious one) IP address changes, rule is obsolete. Every single admin out there must have thought of TCP wrappers by now…

But Webmin being Webmin, you have a problem that there is no documentation that tells you what Perl modules you need for what functionality. So, if you want SSL enabled, you have to have Net::SSLeay, otherwise you’ll never manage to enable SSL. This took me few hours to figure out. So, this time when I needed the TCP wrappers support, I knew what to look for.

Official Webmin documentation tells us that we can, but there is no such button on that page… Off we go to look for perl modules… So finally I found that Webmin needs libwrap which is provided by Authen::Libwrap module. So I used the build servers in my company, and produced perl-Authen-Libwrap RPM package 🙂 So all you folks out there using Webmin on CentOS/RHEL please don’t forget to:

# yum install perl-Net-SSLeay perl-Authen-Libwrap

PS. If anyone wants the package (Authen::Libwrap) it’s freely available from SRCE repositories:


You’ll hopefully find some other cool stuff there too…

Categories: Linux Tags: , ,
  1. December 3, 2013 at 3:34 pm

    Webmin in the Perl Modules section tells you which modules are needed and which aren’t installed. All you have to do is look. You then install any missing ones usually via the Perl Modules installer. You can specify in the installer where it should look including the Perl repos as well as others.

    Ubuntu however is different in that you need to install the following so it works

    apt-get install libwrap0 libwrap0-dev

    hope that helps Ubuntu users

    • December 3, 2013 at 4:04 pm

      I’m not a webmin user, I’m just administering it for windows-based LAMP developers, to ease them some unix operations, so I don’t know much about Webmin internals… Thank you for your comments.

  2. WhatYouNeed2Know
    January 20, 2014 at 3:11 am

    This post is all bullshit and its bad for the internet. Ever visit to the Install Modules section??? It tells you what modules to install and for what functions – even installs them with the click of a mouse. NetSSLeay will prompt for install when visiting Webmin Configuration >>> SSL Encryption. Do some simple research before posting useless information next time.

    • January 20, 2014 at 11:25 am

      Thank you for your comment, I’m really glad that my blog is useful to you. Hope you come back and read new articles 😉

  3. claude
    April 1, 2015 at 3:05 pm

    You probably hate webmin as much as I hate cpanel. That being said, I always install webmin as an unintrusive “side” tool that eases some of my tasks. Quite handy.

    That was probably a bad day …;)

    thx for the infos

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