linkchecker python3-virtualenv python-virtualenv xvfb iceweasel \
libgnutls28-dev python3-dev vim cadaver cython gnupg dirmngr \
libsecret-1-dev r-base r-cran-testthat libxml2-dev pandoc \
- python3-setuptools python3-pip openjdk-8-jdk bsdmainutils && \
+ python3-setuptools python3-pip openjdk-8-jdk bsdmainutils net-tools&& \
apt-get clean
ENV RUBYVERSION_MINOR 2.3