Apache reverse proxy with ProxyPass how to

First install and enable Apache reverse proxy module (mod_proxy) using apt-get (ubuntu, debian, etc):

~> sudo apt-get install libapache2-mod-proxy-html
~> a2enmod proxy_http

Edit your virtual host:

Configure the module to allow connections from your network, edit /etc/apache2/mods-enabled/proxy.conf

Restart apache and you are ready to go!.

Possible errors you could get

If you get this error in /var/log/apache2/error.log :

[error] [client 192.168.56.1] client denied by server configuration: proxy:http://127.0.0.1:28017/folder/

You have to check the "Allow" directive in /etc/apache2/mods-enabled/proxy.conf  remember to allow your network!!!.

If you get this error in /var/log/apache2/error.log :

[warn] proxy: No protocol handler was valid for the URL /api/. If you are using a DSO version of mod_proxy, make sure the proxy submodules are included in the configuration using LoadModule.

you should remember to enable the module:

~> a2enmod proxy_http