\documentclass[unknownkeysallowed]{book}
\usepackage{german}
\usepackage[utf8]{inputenc}
%\usepackage{lxextras}
\usepackage{listings,color}
\lstset{keywordstyle=\color{blue}}

\begin{document}

\title{Linux Entwicklung}
\maketitle

\tableofcontents
\pagebreak