FAQforge provides answers for frequently asked questions for the Linux-, MAC and Windows operating systems.

If all your visitors shall access your website with a URL like www.domain.com and not without www, use the following apache rewrite rule for redirecting them.

RewriteEngine On
RewriteCond %{HTTP_HOST} !^www
RewriteRule (.*) http://www.%{HTTP_HOST}$1 [L,R]

The apache rewrite rule can be added in a .htaccess file in the website root directory or if you use ISPConfig 2 or 3, you can also add the rwrite rule into the apache directives field of the website.

If you run a firewall on your Linux server and want to use passive FTP connections, you have to define the passive port range in pure-ftpd and your firewall to ensure that the connections dont get blocked. The following example is for pure-ftpd on Debian or Ubuntu Linux and ISPConfig 3:

1) Configure pure-ftpd
echo "40110 40210" > /etc/pure-ftpd/conf/PassivePortRange
/etc/init.d/pure-ftpd-mysql restart

2) Configure the firewall. If you use ISPConfig 3 on my server to configure the bastille firewall, you can add the nescessera port range in the ISPConfig firewall settings.

Change the list of Open TCP ports from:




and then click on "Save".

How to redirect an HTTP connection to HTTPS in apache webserver

Tuesday, October 6, 2009 - posted by Till

Http connections can be redirected to https with the apache mod_rewrite module, which should be available in every apache installation. Create a file with the name .htaccess in the website root directory which contains the following lines:

RewriteEngine On
RewriteCond %{HTTPS} off
RewriteRule (.*) https://%{HTTP_HOST}%{REQUEST_URI}

If you use ISPConfig 2 or 3, you can add these lines also in the apache directives field of  the website settings form instead of adding them to a .htaccess file. But the approach with the .htaccess file will work on ISPConfig as well.

Is there a recommended Linux distribution for ISPConfig 3?

Monday, October 5, 2009 - posted by Till

ISPconfig 3 is developed on Debian Linux, this means that Debian is the most tested Linux distribution for ISPConfig. Additionally, Debian has almost all required software packages for ISPConfig in its main repositories without the need to compile them manually and Debian has proven to be very stable in Server enviroments.

This leads to my personal recommendation to use Debian Linux for ISPConfig.

Sometimes you need a specific file from a Debian .deb package e.g. because you deleted a file from your system or the installation of a package is broken in that way that it can not be reinstalled without adding the missing file first. This FAQ shows you how to download the .deb file from the Debian or Ubuntu repository and then exctract its contents.

Download the dpkg file. In this example, I will download the courier-athlib:

cd /tmp
aptitude download courier-authlib

Now extract the .deb package into the directory /tmp/extract/:

dpkg-deb -x *.deb /tmp/extract/

How to enable the query log in MySQL

Wednesday, September 30, 2009 - posted by Till

To debug applications which use a mysql database, it comes in handy to enable the query log to get all SQL queries that were sent to the database.  Open the MySQL configuration file (my.cnf)

vi /etc/mysql/my.cnf

and add the line:


in the [mysql] section of the file. Depending on the Linux distribution that you use, the my.cnf file can be /etc/my.cnf or /etc/mysql/my.cnf.

Afterwards restart mysql to apply the new the configuration:

/etc/init.d/mysql restart

After running a system upgrade on your Ubuntu based ISPConfig 3 server, it might happen that aptitude overwrites some config files from postfix especially the main.cf file. To fix this, download the latest ISPConfig 3 installer, unpack it and run the update.php script. Choose "yes" when the updater asks if the services shall be reconfigured. ISPConfig will replace the configuration files that had been modified by the ubuntu upgrade.

cd /tmp
wget http://www.ispconfig.org/downloads/ISPConfig-3-stable.tar.gz
tar xvfz ISPConfig-3-stable.tar.gz
cd ispconfig3_install/install
php -q update.php

How to add a root SSL certificate in ISPConfig 2

Wednesday, September 23, 2009 - posted by Till

Most SSL authorities (like godaddy or instantssl) send you a root certificate which has to be installed beside the SSL certificate to proove that the SSL cert is signed from a trusted authority. To add such a root SSL certificate in ISPConfig, copy the file to the ssl subfolder of the website and then add this line into the apache directives field of the website in ISPConfig:

SSLCACertificateFile /var/www/www.yourdomain.tld/ssl/ca.txt

The path to the root certificate file has to be changed to match the path on your system.

Install postfix with MySQL support on CentOS 5.3 (64Bit)

Monday, September 21, 2009 - posted by Till

The following article explains the steps to compile postfix MTA with MySQL support on CentOS 5.3 as e.g. needed for ISPConfig 3.

Remove the postfix package from CentOS which does not has MySQL support:

/etc/init.d/postfix stop
rpm -e --nodeps postfix

Download the postfix source RPM and install it:

cd /tmp
wget http://mirror.rackspace.com/CentOS/5.3/os/SRPMS/postfix-2.3.3-2.1.el5_2.src.rpm
rpm -i postfix-2.3.3-2.1.el5_2.src.rpm

Edit the spec file to enable MySQL support.

vi /usr/src/redhat/SPECS/postfix.spec

and change the line:

%define MYSQL 0


%define MYSQL 1

Install a few prerequisites before we build the new postfix RPM package

yum install pcre-devel mysql-devel

Build the postfix RPM with MySQL support:

rpmbuild -ba /usr/src/redhat/SPECS/postfix.spec

and install it.

cd /usr/src/redhat/RPMS/x86_64
rpm -i postfix-2.3.3-2.1.x86_64.rpm

Start postfix and configure it to be started at boot time:

/etc/init.d/postfix start
chkconfig --levels 235 postfix on

The language of the generated webslizer statistics is statically compiled into the webalizer binary. To change the language, webalizer has to be recompiled. In the following example, I will recompile webalizer to change the language to german.

Uninstall webalizer and install the GD library:

apt-get remove webalizer
apt-get install libgd2-xpm-dev

Download the latest webalizer sources and uncompress the tar archive:

cd /tmp
wget http://archive.mgm51.com/mirrors/webalizer-files/webalizer-2.01-10-src.tgz
tar xzf webalizer-2.01-10-src.tgz
cd webalizer-2.01-10

Reconfigure and compile webalizer

./configure --with-language=german
make install

Create a symlink so that other applications find the webalizer binary in the common place

ln -s /usr/local/bin/webalizer /usr/bin/webalizer


rm -f /tmp/webalizer-2.01-10-src.tgz
rm -rf /tmp/webalizer-2.01-10

Thanks to planet_fox for this FAQ.