If you are a developer and you’re working with several subdomains for development purposes, you can create a single virtualhost, without the need to add subdomains and restart/reload the apache web server.
Directory structure (example):
/var/www /var/www/project1.unixteacher.org /var/www/project2.unixteacher.org /var/www/project3.unixteacher.org /var/www/development.unixteacher.org
One single virtualhost for any subdomain:
<VirtualHost *> DocumentRoot /var/www ServerName unixteacher.org ServerAlias *.unixteacher.org CustomLog logs/access_log combined ErrorLog logs/error_log RewriteEngine On RewriteMap lowercase int:tolower RewriteRule ^/(.*)$ /var/www/${lowercase:%{SERVER_NAME}}/$1 </VirtualHost>