Free Linux Tutorials

Setup VNC Server in Fedora

“Virtual Network Computing (VNC) is a desktop protocol to remotely control another computer. It transmits the keyboard presses and mouse clicks from one computer to another relaying the screen updates back in the other direction, over a network.” -WikiPedia-
This article describes in brief how to configure VNC server instances for one or multiple users on a remote machine, how to use VNC to start graphical applications on boot and finally how to enhance security by connecting to the server through encrypted SSH tunnels.

The DNS server was deployed in CentOS release 4.4, ,kernel ver. 2.6.9-42.0.3.Elsmp, Intel Xeon 3.2 GHz 2G RAM

Software Requirements
Any Linux/Unix flavors

Packages needed:

a.    Daemontools  (http://cr.yp.to/daemontools.html)
b.    UCSPI-TCP (http://cr.yp.to/ucspi-tcp.html)
c.    Djbdns (http://cr.yp.to/djbdns.html)
d.    Dnscache (http://cr.yp.to/dnscache.html)
e.    Tinydns (http://tinydns.org)
f.    Vegadns ( for web interface of tinydns, optional) (http://www.vegadns.org/)
g.    MySQL server (optional)
h.    Php, gcc, apache web server, perl, patch

Before installing djbdns , install daemontools and ucspi-tcp

1.DAEMONTOOLS

a. Create a /package directory:
mkdir -p /package
chmod 1755 /package
cd /package
b. Download the package daemontools-0.76.tar.gz into /package. Unpack the daemontools package:
tar zxvf daemontools-0.76.tar.gz

I.    Introduction

This document will discuss installation and configurations how-to on setting up POP3 using Dovecot (www.dovecot.org), SMTP using Sendmail (www.sendmail.org), Email Security System using MailScanner (www.mailscanner.info)  and a Web-based front-end to MailScanner using Mailwatch (mailwatch.sourceforge.net)

II.    Planning the Installation

System Requirements:

a.    Linux Operating System (Kernel 2.2 and later)
b.    Apache Web Server
c.    Perl and perl modules
d.    GCC
e.    MySQL
f.    Vi editor
g.    PHP (w/ MySQL & GD Support)
h.    DBD
i.    DBD-MySQL
j.    wget
k.    unzip/unrar
l.    Dovecot
m.    Sendmail
n.    MailScanner/ClamAV/SpamAssassin
o.    Mailwatch

The procedure below was tested successfully on CentOS.  The same thing was also implemented on my BSD box and works as well.

Squid is a caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. It reduces bandwidth and improves response times by caching and reusing frequently-requested web pages. Squid has extensive access controls and makes a great server accelerator. It runs on Unix and Windows and is licensed under the GNU GPL.

MailWatch for MailScanner is a web-based front-end to MailScanner and features include displays of inbound/outbound mail queue size, load Average and today’s totals for messages, spam, viruses and blocked content on each page header, Quarantine management allows you to release, delete or run sa-learn across any quarantined messages etc.

Tested on CentOS 4.4, MailScanner ver. 4.57.6, Sendmail-8.13

Requirements:

a.    Working MailScanner setup
b.    MySQL
c.    Apache
d.    PHP (w/ MySQL and GD Support)
e.    Perl
f.    DBD
g.    DBD-MySQL

For those who uses java server pages via Tomcat server on Linux, providing secure transaction on your website thru SSL protocol is a must.  By this of course  we need to install a CA assigned certificate on the server.

The procedure below is a sample installation of  SSL certificate which tested working on my site .

Prerequisites:

Linux (tested on CentOS 4.3 x64 and later)
OpenSSL
JDK 1.5 ( J2SE 1.5.09 at the time of this writing)
Tomcat server (Apache Tomcat 5.5.20 binary version for linux)

SETUP

1.    Linux
It is assumed that CentOS is ready and updated before installation of other packages.

This is a continuation procedure for AWStats installation.

PROCEDURES:

GeoIP Information will show country information in AWStats.

1.    Download the current GeoLite Country from the internet
1. #wget http://www.maxmind.com/download/geoip/database/GeoIP.dat.gz

2.    Create GeoIP directory
# mkdir /usr/local/share/GeoIP

3.    Move data files to directory and unzip.
#mv GeoIP.dat.gz /usr/local/share/GeoIP/
#gunzip /usr/local/share/GeoIP/GeoIP.dat.gz

4.    Install the GeoIP program
#wget http://www.maxmind.com/download/geoip/api/c/GeoIP-1.4.3.tar.gz
#cd /usr/local/src
#tar zxvf GeoIP-1.4.3.tar.gz
#cd /usr/local/src/GeoIP-1.4.3
#./configure
#make
#make check
#make install

#vi /etc/ld.so.conf
add the line:
/usr/local/lib

#ldconfig

5.    Install Geo::IP Perl Module

#wget http://www.maxmind.com/download/geoip/api/perl/Geo-IP-1.27.tar.gz

Here are the steps in installing and configuring AWstats in Tomcat Web Server

STEPS:

1.    Download awstats.war from the internet
2.    Since Tomcat disabled by default the CGI executions, we need to enable it by renaming the file servlets-cgi.renametojar to servlets-cgi.jar
Example:
[Tomcat_installation_path] = /usr/local/apache-tomcat-5.5.20

#cd /usr/local/apache-tomcat-5.5.20/server/lib
#mv servlets-cgi.renametojar servlets-cgi.jar

3.    Install AWStats
Since it is already a .war file, no need to install it by hand, you just need to copy this file to [Tomcat_installation_path]/webapps folder

#cp awstats.war [Tomcat_installation_path]/webapps

It would create an [Tomcat_installation_path]/webapps/awstats folder after copied.

4.    Configure AWStats
Let say our domain is www.mydomain.com

Here are the steps in installing AWstats on Apache Web Server as your web log analyzer and statistics:

STEPS:

Assuming VirtualHost setting is already added on the httpd.conf, and the log is customized already for a combined log.

Example:
#<VirtualHost support.freelinuxtutorials.com:80>
ServerAdmin webmaster@support.freelinuxtutorials.com
DocumentRoot /home/www/support.freelinuxtutorials.com
ServerName support.freelinuxtutorials.com
ErrorLog /var/log/httpd/support.freelinuxtutorials.com-error_log
CustomLog /var/log/httpd/support.freelinuxtutorials.com-combined_log combined

If not httpd.conf should be modified to customized the log of a particular website

CustomLog /yourlogpath/yourlogfile common
to
CustomLog /yourlogpath/yourlogfile combined

1.    Download the latest stable awstats.tar.gz  from the internet

#cd /usr/local/
#wget http://prdownloads.sourceforge.net/awstats/awstats-6.7.tar.gz

2.    Uncompress the tarball file and rename the directory to awstats

Freeradius and MySQL

Software Requirements:

Any Linux distro, kernel 2.4xx-later(tested in CentOS,Fedora Core,RH)
MySQL Server 4.xx-5.xx
GCC compiler
vi editor

1.    Get the latest freeradius source code tarball from www.freeradius.org or get the rpm package using “yum”

2.    Unpack the tarball and install it.
#tar zxvf freeradius-xxx.tar.gz
#cd freeradius
#./configure
#make
#make install

3.    Start with a simple config using the standard text files, this will test if the Freeradius installed is working or not

a.    Edit /etc/raddb/clients.conf to enter the details of the NAS unit.You can enter “localhost” for testing purposes
b.    Edit /etc/raddb/users and create a sample user account