Removing index.php from codeigniter+LAMP

1. Create a .htaccess file in your application root directory.
    <IfModule mod_rewrite.c>
      RewriteEngine on
      RewriteCond $1 !^(index\.php|public|\.txt)
      RewriteCond %{REQUEST_FILENAME} !-f
      RewriteCond %{REQUEST_FILENAME} !-d
      RewriteRule ^(.*)$ index.php?$1
    </IfModule>

    <IfModule !mod_rewrite.c>
      # If we don't have mod_rewrite installed, all 404's
      # can be sent to index.php, and everything works as normal.
      # Submitted by: ElliotHaughin

      ErrorDocument 404 /index.php
    </IfModule>

    # Disable server signature
    ServerSignature Off

    # DEFLATE by type - html, text, css, xml
    AddOutputFilterByType DEFLATE text/html text/plain text/css text/xml
 
    # DEFLATE by type - javascript
    AddOutputFilterByType DEFLATE application/x-javascript application/javascript text/javascript text/x-js text/x-javascript
 
    # DEFLATE by extension
    AddOutputFilter DEFLATE js css htm html xml

2. Change configurations.
    $config['base_url']    = 'http://'.$_SERVER['HTTP_HOST'].'/';
    $config['index_page'] = '';

3. Enable mod_rewrite module on server
    sudo a2enmod rewrite
    
4. Restart apache
    sudo service apache2 restart
    
5. To use mod_rewrite from within .htaccess files edit the default VirtualHost.
    sudo nano /etc/apache2/sites-available/000-default.conf
    
6. Search for “DocumentRoot /var/www/html” and add the following lines directly below:
    <Directory "/var/www/html">
      AllowOverride All
    </Directory>
    
7. Restart apache
    sudo service apache2 restart