Apache2

Web Server for linux.
Paths:
/etc/apache2/sites-available
/etc/apache2/sites-enabled (symbolic links to sites-available/*.conf files)

Virtual Hosts

Apache allows to have multiple web sites on the same server. To do this go to sites-available and create a
.conf file for each host you whant containing the following:

 <VirtualHost *:80>
    ServerAdmin rafael@herrerosolis.com
    DocumentRoot /var/www/webfolder
    ServerName www.yourwebpagename.com
    ServerAlias www.yourwebpagename.com

    ErrorLog /var/www/yourwebfolder/logs/error.log
    
    # Posible values include: debug, info, notice, warn, error, crit.
    # alert, emerg.

    CustomLog /var/www/yourwebfolder/logs/access.log combined

 </VirtualHost>

You should also enter in your domain administration panel and create the CNAMES to redirect trafic
to the public ip of this server

Basic SSL VirtualHost:

<VirtualHost *:80>
          ServerName home.rra.lan
          ServerAdmin webmaster@rra.lan
          DocumentRoot /var/www/home.rra.lan
          
          Redirect permanent / https://home.rra.lan
          ErrorLog ${APACHE_LOG_DIR}/error.log
          CustomLog ${APACHE_LOG_DIR}/access.log combined
  </VirtualHost>
  <VirtualHost *:443>
          ServerName home.rra.lan
          ServerAdmin webmaster@rra.lan
          DocumentRoot /var/www/home.rra.lan
          ErrorLog ${APACHE_LOG_DIR}/error.log
          CustomLog ${APACHE_LOG_DIR}/access.log combined
          
          SSLEngine on
          SSLCertificateKeyFile /etc/ssl/private/home.rra.lan.key
          SSLCertificateFile /etc/ssl/certs/home.rra.lan.crt
          SSLCertificateChainFile /etc/ssl/certs/FreeIPA-CA.crt
  </VirtualHost>
  

Redirect HTTP to HTTPS

sudo nano /etc/apache2/sites-available/redirect_HTTP_to_HTTPS.conf

<VirtualHost *:80>
          RewriteEngine on
          RewriteRule ^ https://%{SERVER_NAME}%{REQUEST_URI} [END,QSA,R=permanent]
  </VirtualHost>

sudo ln -s /etc/apache2/sites-available/redirect_HTTP_to_HTTPS.conf /etc/apache2/sites-enable/redirect_HTTP_to_HTTPS

Authentication

Create user account with:

htpasswd -c /usr/local/apache/passwd/passwords rbowen

Protect with the directory directive:

<Directory "/usr/local/apache/htdocs/secret">
      AuthType Basic
      AuthName "Restricted Files"
      # (Following line optional)
      AuthBasicProvider file
      AuthUserFile "/usr/local/apache/passwd/passwords"
      # Require user rbowen
      Require valid-user
  </Directory>

Reverse Proxy

a2enmod proxy proxy_http  # HTTP
a2enmod proxy proxy_ftp   # FTP
a2enmod proxy proxy_html  # rewrite HTML links in proxy address space
a2enmod proxy proxy_ajp   # Tomcat
a2enmod proxy
a2enmod rewrite
a2enmod deflate
a2enmod headers
a2enmod proxy_balancer
a2enmod proxy_connect

VirtualHost ProxyPass

<VirtualHost *:*>
    ProxyPreserveHost On

    # Servers to proxy the connection, or;
    # List of application servers:
    # Usage:
    # ProxyPass / http://[IP Addr.]:[port]/
    # ProxyPassReverse / http://[IP Addr.]:[port]/
    # Example: 
    ProxyPass / http://0.0.0.0:8080/
    ProxyPassReverse / http://0.0.0.0:8080/

    ServerName localhost
</VirtualHost>

apachectl

sudo apachectl configtest

https://httpd.apache.org/docs/2.4/programs/apachectl.html

See more options at:

https://httpd.apache.org/docs/2.4/es/howto/auth.html

https://www.digitalocean.com/community/tutorials/how-to-use-apache-http-server-as-reverse-proxy-using-mod_proxy-extension