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How to Configure Apache2 as Forward and Reverse Proxy

This is a cook recipe to configure an Apache2 as a forward and reverse proxy on Debian-based Linux systems like Ubuntu or Debian itself.


It is assumed that the apache2 package is already installed on your system. For the proxy feature, we have to install the Apache2 module libapache2-mod-proxy-html on the system and activate theses Apache modules. At the end, Apache2 has to be restarted, so that the modules can be used.

sudo apt-get install libapache2-mod-proxy-html
sudo a2enmod proxy
sudo a2enmod proxy_html
sudo a2enmod proxy_http
sudo service apache2 restart

Configuration Forwarding and Rewarding

We want to forward the URL request to and rewarding to for every response.

For that, we have to create a so-called Virtual Host in Apache2. It is easiest to copy the configuration of the default one and adjust it.

cd /etc/apache2/sites-available
sudo cp 000-default.conf jenkins_ci.conf

It is best practice to create one conf file per Virtual Host. Adding and removing Virtual Host is easier with this approach.

The content of the Virtual Host configuration should look similar to the following one:


ServerAdmin webmaster@localhost

ProxyRequests Off
<Proxy *>
Order deny,allow
Allow from all
ProxyPass / http://localhost:8083/
ProxyPassReverse / http://localhost:8083/

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

We have to add the host name (in this case to the line 1 and 2, so that Apache2 knows for which host name is this Virtual Host. In line 11 and 12 the mapping is configured (in this case, everything that call the host name directly should be forwarded to http://localhost:8083; the opposite for rewarding).

At the end this configuration has to be enabled.

sudo a2ensite jenksin_ci.conf
sudo service apache2 reload


Further Information




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How to Install Serverspec in the Current Version on Ubuntu 14.04 LTS (Trusty)

If you google “serverspec install ubuntu”, you find the information that a package called ruby-serverspec in the standard package repository can be used to install Serverspec on an Ubuntu 14.04 LTS based system. Unfortunately, this package installs an outdated version of Serverspec. The next point is that if you try to install the newest version of Serverspec with gem (that’s the way that it is described on the Serverspec homepage), you will get the following error message:

~> sudo gem install serverspec
ERROR:  Error installing serverspec:
net-ssh requires Ruby version >= 2.0.


The problem is, when you install Ruby with sudo apt-get install ruby, the package manager installs Ruby in the version 1.9.1 .

Therefore, the next sections explain how to install Ruby and Serverspec in the newest version on an Ubuntu 14.04 LTS based system. Let’s start with Ruby that is required for Serverspec.

Ruby Installation

The cloud hosting service Brightbox provides Ruby package repositories for several Ubuntu versions and several Ruby version. I chose the repository for Ruby 2.3 packages, so the installation steps are:

~> sudo apt-get install software-properties-common
~> sudo apt-add-repository ppa:brightbox/ruby-ng
~> sudo apt-get update
~> sudo apt-get install ruby2.3
~> ruby --version
ruby 2.3.0p0 (2015-12-25 revision 53290) [x86_64-linux-gnu]

Serverspec Installation

Now, we can install Serverspec like it is explained on the Serverspec homepage. In my case, I had to install rake separately.

~> sudo gem install serverspec rake


  1. Serverspec Homepage
  2. Brightbox Ruby package repositories for Ubuntu documentation