Create Local Sub-Domain

Step1: Create file devtest.com.conf inside /etc/apache2/sites-available .
Step2: Paste below contents in file.

<VirtualHost *:80>
        # The ServerName directive sets the request scheme, hostname and port that
        # the server uses to identify itself. This is used when creating
        # redirection URLs. In the context of virtual hosts, the ServerName
        # specifies what hostname must appear in the request's Host: header to
        # match this virtual host. For the default virtual host (this file) this
        # value is not decisive as it is used as a last resort host regardless.
        # However, you must set it for any further virtual host explicitly.
        #ServerName www.example.com


################## Virtual Host setting #####################
ServerAdmin webmaster@localhost
ServerName devtest.com
        ServerAlias www.devtest.com
        DocumentRoot /var/www/html/foldername
        <Directory /var/www/html/foldername/>
                Options Indexes FollowSymLinks MultiViews
                AllowOverride All
                Order allow,deny
                allow from all
        </Directory>




########ServerAdmin webmaster@localhost
#######DocumentRoot /var/www/html

       # Available loglevels: trace8, ..., trace1, debug, info, notice, warn,
        # error, crit, alert, emerg.
        # It is also possible to configure the loglevel for particular
        # modules, e.g.
        #LogLevel info ssl:warn

       ErrorLog ${APACHE_LOG_DIR}/error.log
        CustomLog ${APACHE_LOG_DIR}/access.log combined

       # For most configuration files from conf-available/, which are
        # enabled or disabled at a global level, it is possible to
        # include a line for only one particular virtual host. For example the
        # following line enables the CGI configuration for this host only
        # after it has been globally disabled with "a2disconf".
        #Include conf-available/serve-cgi-bin.conf
</VirtualHost>

# vim: syntax=apache ts=4 sw=4 sts=4 sr noet  

Step3:Run below commands.
 sudo a2ensite local.vivendo.com.conf
 sudo service apache2 restart