Webmin is a web-based interface for system administration of Unix/Linux systems. It allows administrators to perform tasks like user account management, Apache configuration, DNS configuration, and file sharing through a web browser-based interface. Webmin uses modules to add new administrative features and supports over 25 Unix/Linux operating systems. It can be installed by downloading packages from its website and requires Perl 5 to run. Common modules allow administration of users/groups, cron jobs, software packages, filesystems, and running processes.

1. Introduction

2. System Administration With
Webmin
A brief overview of
new era administration
tool
Prepared by
Henry Batula
12539114
Ni Xiao
12640223
Peter Greenup
12645736

3. What is Webmin?

Webmin is a web-based interface for system
administration for Unix/Linux. Using any
browser that supports tables and forms (and
Java for the File Manager module), you can
setup user accounts, Apache, DNS, file
sharing and so on

Often considered equivalent to windows
control panel
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4. What is Webmin (cont’d)




It is a user administration tool written by Jamie
Cameron in Perl that is designed to be lightweight,
functional, and easily extensible
It has been translated to 14 languages at the moment
It has been embraced by a number of hardware and
operating system vendors as the default system
administration tool(Linux-Mandrake 7.0)
It is extremely portable, offering support for more
than 25 different Unix/Linux Operating Systems
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5. What is Webmin? (cont’d)

It is very easily extended to support new
features and options, due to it's open and well
documented API
 It also happens to be a fast and easy to use
tool for general Unix/Linux system
administration
 It allows easy addition of new modules
without changing any of the existing code
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6. What is required

A simple web server, and a number of CGI
programs which directly update system files
like /etc/inetd.conf and /etc/passwd.

The web server and all CGI programs must be
written in Perl version 5. This means that you
only need a Perl binary to run it.
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7. Who Webmin is For

It is an excellent tool for both novice and
experienced system administrators

When run from a local machine, it can help
new users become familiar with the
capabilities of a Linux system.
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8. Sections within Webmin

The individual modules of webim are found
in 5 different sections.
•
•
•
•
•
•
Webmin
System
Servers
Networking
Hardware
and Others
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9. Interface of Webmin
9

10. Webmin modules




It uses modules, which are similar to plug-ins, and
easily allow you to extend the base functions of
Webmin.
It is divided into a number of modules that each
allows to administer a single aspect of system
There are Currently 127 Modules
The standard modules provide a graphical interface
for: Apache, Squid, Bind, NFS, man pages,
Sendmail, Postfix, Samba
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11. Common Modules from Webmin 0.74 Modules
admi Scheduled Cron Jobs
n
NFS Exports
BIND 4 DNS Server
Internet Services and Protocols
Bootup and Shutdown Actions
Samba Windows File Sharing
Disk and Network Filesystems
Users, Groups and Passwords
Partitions on Local Disks
Running Processes
Webmin Configuration
Disk Quotas
Software Packages
Webmin Users
PPP Usernames and Passwords
Apache Webserver
Printer Administration
BIND 8 DNS Server
Sendmail Configuration
Squid Proxy Server
File Manager
Network Configuration
DHCP Server
Majordomo List Manager
Firewall Configuration
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12. Supported Operating Systems
Sun Solaris
NetBSD
DEC/Compaq OSF/1
Cobalt Linux
Mandrake Linux
Mandrake Linux Coprporate Server
Caldera OpenLinux eServer
BSD
IBM AIX
Redhat Linux
HP/UX
SCO UnixWare
Slackware Linux
SGI/UX
SCO OpenServer
SuSE Linux
Corel Linux
TurboLinux
MSC Linux
LinuxPPC
Xlinux
Cendio LBS Linux
Linux From Scratch
Trustix
Ute Linux
Lanthan Linux
Trustix
Cendio LBS Linux
FreeBSD
OpenBSD
Debian Linux
SGI Irix
Mac OS Server X
Delix DLD Linux
Conectiva Linux
12
Some of
Webmin
supported
operating
systems

13. Installation of Webmin

14. Installation of Webmin

Firstly check to see if it is currently installed. Do a
search for the webmin module. Webmin is included
with many linux operating systems, so may appear
on an installation disk.

Installation requires that Perl 5 is already installed (this is usually
included with most versions of linux).
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15. Installation (Cont’d)

L-M animation of
finding package.

(you may need to
wait a few
seconds for the
animation to
start).
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16. Installation of Webmin (Cont’d)

Otherwise it can be downloaded from www.webmin.com There
are a couple of different versions available, choose the one
which best suits your current system. Approximate file size is
3.6 to 4MB

If installing the RPM package run the command:
rpm -U webmin-0.87.rpm


If using the Solaris package run the following command:
pkgadd -d webmin-0.87.pkg
Begins with root username and password.
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17. Installation Checks



Please wait for
animation of
Webmin after install.
Webmin is seen as a
new service in the
linuxconf control
panel
Ktail messages
shows that webmin
starts automatically
after install.
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18. Installation Checks (Cont’d)

Check the
following functions
for Webmin:
Stop
Start
Restart

The "messages"
log will show the
status.
Please wait for
animation.

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19. Logging on

Open a web browser such as Netscape or IE,
on any machine with access to the server you
wish to log onto.
 Browse to the port 10000 of the IP address or
hostname. (as shown below)
19

20. Logging on (Cont’d)

Animation of
logging onto the
service.
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21. Example Modules
A brief description of some of the
commonly used modules.

22. Webmin main tab
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23. Webmin Configuration

This section give the user control of the webmin setup.
Allowing the adjustment to the following areas.





IP address control
Password settings
Interface control
Language used
Modules included
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24. Webmin Configuration (Cont’d)

Animation of
access to IP
address
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25. System Tab
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26. System modules

Bootup and shutdown
• as name suggests

Users and Groups
• displays all users names, id’s home directory etc.
• allows editing of user settings

Manual Pages
• extensive help pages
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27. System modules (Cont’d)

Cron Jobs
• This is one process that is greatly simplified by the
webmin interface.
• Cron is a daemon that runs constantly on most unix
machines. Allows for the scheduling of processes to
be run at set times eg. backups or scans.
• Lists all scheduled jobs
• Control access of users to cron jobs
• Add a new scheduled item
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28. System modules (Cont’d)

Cron job
screen
sample
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29. System modules (Cont’d)

Software packages



View all installed
packages
Search for
installed packages
Install new
packages
29

30. System modules (Cont’d)

30
Install
package
screen
sample

31. System modules (Cont’d)

FileSystem Management

It provides permission to
•
•
•
•
•

mount,
dismount,
create,
edit, and
delete 14 different filesystems
To get started,
• click the Disk and Network Filesystems

Webmin displays a list of available filesystems
31

32. System modules (Cont’d)

File System Management

Display screen will show the
• mount point,
• filesystem type,
• device or location whether it is
• mounted, and
• listed in /etc/fstab.

To edit one of the listed file system,
• click its mount point, listed in the first column
32

33. System modules (Cont’d)

File System Management

To add or create a new filesystem,
• first select its type from the drop-down list box
• then click the “Add” button


The Create Mount and the Edit Mount screens are similar
except that it has to be filled it out
Select the “Don't Save” button
• to prevent an entry for the swapfile from being added to /etc/fstab
• the swapfile will be named, imaginatively, /tmp/swapfile

Click the “Create” button to activate the changes
33

34. System modules (Cont’d)


The display screen
After making changes,
click
•
•
the “Apply” button to
update the /etc/fstab file
activate the changes.
34

35. System modules (Cont’d)

Running Processes

Webmin's process manager
• resembles a browser-based version of the famous top utility
• allows to execute an arbitrary command
• screen is obtained by
• clicking the “Running Processes” icon

The display is sorted either
•
•
•
•
by process ID or by selecting the link of
username,
memory usage, and
CPU time consumed
35

36. System modules (Cont’d)
 Running

Processes
Can be used after filling in the searching criteria
• by clicking the corresponding search button
Criteria
Description
Owned by
Enter a user name
Matching
Enter a string
Usage % CPU
Enter between 0 and 100
Using filesystem
Select a filesystem
Using file
Enter a filename
36

37. System modules (Cont’d)
 Running

Processes
Can be used to change process priority
• click a PID from either the main listing or a search
screen
• select a new priority (called a nice level)
• then click the “Change” button
37

38. System modules (Cont’d)
 Running

Processes
Common process signals with webmin
Signal
Description
INT
Sends a keyboard interrupt (Ctrl+C)
QUIT
Terminates the process.
ABRT
Terminates the process and creates a memory
dump
KILL
Terminates the process
TERM
Terminates the process
STOP
Stops the process, but does not kill it
CONT
Resumes a stopped process
38