Building a Server Appliance with Trustix Secure Linux and Webmin

One of my fellow geeks at work recently showed me a Red Hat box on which he configured Webmin. (Thanks Tom C.) This is an open source web-based administration tool for UNIX, sponsored by Caldera and made available under the BSD license. Webmin's homepage is http://www.webmin.com. It runs on a variety of UNIX flavors, not just Linux. This allows us to have a common GUI for all of our UNIXish systems, whether they're running Linux, BSD, or whatever. Anyway, I had long wanted to try out Webmin and this finally got me to stop procrastinating. I decided to combine Webmin with Trustix and see how they worked together.

One thing I had to do first, though, was to enable a way to get Webmin onto the Trustix box. I could have used the standard CLI ftp client to download it directly, but I found it easier to download Webmin onto a Windows machine and transfer it over to the Trustix server using Samba. Since I've done some hacking with Samba, and I want to use this PC as a fileserver for Windows clients anyway, I created a Samba share on the machine by manually editing the smb.conf file and adding my regular user's home directory as a network share.

A bare bones smb.conf file that will allow this looks like:

<begin smb.conf>

#====== Global Settings =============

[global]

# workgroup = NT-Domain-Name or Workgroup-Name 
workgroup = midearth

# server string is the equivalent of the NT Description field
server string = Trustix Samba Server

# This option is important for security. It allows you 
# to restrict connections to machines which are on 
# your local network. The following example restricts 
# access to two C class networks and the "loopback" 
# interface. For more examples of the syntax see 
# the smb.conf man page
hosts allow = 192.168.10.127.


#======= Share Definitions ==========

[homes]
writable = yes
comment = Home Directories
browseable = no

[frodo]
valid users = frodo
path = /home/frodo
write list = frodo

<end smb.conf>

I then used the smbpasswd command to sync the passwords for my Windows, Linux, and Samba user accounts. E.g.,

root@bagend# su frodo
 frodo@bagend$ smbpasswd New SMB password: (The password is not
   echoed to the screen.)
 Retype new SMB password:
 Password changed for user frodo
 frodo@bagend: exit
 root@bagend#

I then started the Samba daemon (smbd), and the directory showed up on my Win2K box in My Network Places. Starting smbd is done with the following command:

root@bagend# /usr/sbin/smbd start

Then I used ntsysv to select smb as one of the daemons that start automagically on boot.

Readers who need more information on Samba can go to the official website at http://www.samba.org. Also, I've found "Using Samba" from O'Reilly to be a very useful resource. In fact, the whole book is available online at http://www.oreilly.com/catalog/samba/chapter/book/index.html.

After firing up Samba, I was able to copy the Webmin tarball over to the Linux PC and install it. (Although Webmin is available in RPM format, I chose to get it as a UNIX tar.gz file, since the RPMs are not specifically made for Trustix.) After it's copied over and in the right directory (I moved it to /opt), your untar it by:

root@bagend# tar -xvzf webmin-0.86.tar.gz

This created a directory named webmin-0.86 under /opt. You then cd to that directory and run the setup script:

root@bagend# cd webmin-0.86
root@bagend# ./setup.sh

Webmin's interface is in a word, slick. Much like the Cobalt Qube and Rebel Netwinder, it allows you to admin a Linux box through your web browser. Most system administration tasks can be performed through Webmin's default modules, and many third-party add-ons are available. The login screen you get when you first connect to the box through your browser looks like this:

In effect, Webmin allows you to take a regular PC and turn it into a "server appliance." A separate web server, like Apache, is not required, since Webmin installs its own.