\section{Interfaces}
\begin{frame}
   {Firewall Interfaces and Tools}

   \begin{itemize}
      \item
      Command line tools:
      \begin{itemize}
         \item \textbf{iptables}
         \item \textbf{firewall-cmd}
         \item \textbf{ufw}
      \end{itemize}
      \item
      Graphical interfaces
      \begin{itemize}
         \item \textbf{system-config-firewall}
         \item \textbf{firewall-config}
         \item \textbf{gufw}
         \item \textbf{yast}
      \end{itemize}
      \item Other utilities, such as \textbf{shorewall}, exist
      \item
      Command line tools vary less between distributions

   \end{itemize}

\end{frame}

\cprotect\note{

   Configuring your system's firewall can be done by:

   \begin{itemize}
      \item Using relatively low-level tools from the command
      line, combined with editing various configuration files
      in the \filelink{/etc} subdirectory tree:
      \textbf{iptables}, \textbf{firewall-cmd}, \textbf{ufw},
      etc.
      \item Using robust graphical interfaces:
      \textbf{system-config-firewall},
      \textbf{firewall-config}, \textbf{gufw}, \textbf{yast},
      etc.

   \end{itemize}

   We will work with the lower level tools for the following
   reasons:
   \begin{itemize}
      \item They change less often than the graphical ones.
      \item They tend to  have a larger set of capabilities.
      \item They vary little from distribution to distribution,
      while the \textbf{GUI}s tend to be quite different and
      each confined to only one family of distributions.
   \end{itemize}
   The disadvantage is they can seem more difficult to learn
   at first.

   In the following we will concentrate on the use of the
   modern \textbf{firewalld} package, which includes both
   \textbf{firewall-cmd} and \textbf{firewall-config}.  For
   distributions which do not have it by default, it can be
   installed from source rather easily, as we will do if
   necessary in an exercise.

}

\begin{frame}
   {Why we are not working with iptables}

   \begin{itemize}
      \item
      Most firewall installations today are actually using the
      \textbf{iptables} package on the user side.
      \item
      This currently interfaces the same kernel firewall
      implementation code as \textbf{firewalld} which we will
      discuss more.
      \item
      We have decided not to teach \textbf{iptables} because
      it requires much more time to get to useful
      functionality
      \item
      However, \textbf{iptables} is discussed in detail in the
      next course in the \textbf{Linux Foundation} system
      administrator sequence:

      \textbf{LFS311: Linux for System Engineers}

      \item
      See
      \url{https://training.linuxfoundation.org/linux-courses/system-administration-training/linux-for-system-engineers}
   \end{itemize}
\end{frame}

\cprotect\note{

}
