Debian (Ubuntu)
1. Configure Apache2 for Sites :
Before you jump to configure your virtual hosts do not forget to add host names in /etc/hosts file.
your.ip.add.res vritualhost_1.name
your.2.ip.add.res virtualhost_2.name
2. Apache2 needs to be configured to support vhost access to your new sites.
Create vhost site configuration files in /etc/apache2/sites-available/
#
# Virtual hosting configuration for Drupal
#
ServerAdmin [your email address]
DocumentRoot /usr/share/drupal6/
ServerName [your vhost#1 name]