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+\documentclass[a4paper,12pt]{article}
+\usepackage[utf8]{inputenc}
+\usepackage[T1]{fontenc}
+\usepackage{lmodern}
+\usepackage{geometry}
+\geometry{margin=1in}
+\usepackage{listings}
+\usepackage{xcolor}
+\usepackage{parskip}
+
+\lstset{
+  basicstyle=\ttfamily\small,
+  breaklines=true,
+  frame=single,
+  numbers=left,
+  numberstyle=\tiny,
+  keywordstyle=\color{blue},
+  commentstyle=\color{gray},
+  stringstyle=\color{red}
+}
+
+\begin{document}
+
+\title{Basic Configuration of dnsmasq in an Incus Container on Debian with Netplan}
+\author{}
+\date{}
+\maketitle
+
+\section{Introduction}
+This guide provides step-by-step instructions for setting up \texttt{dnsmasq} as a DNS and DHCP server in an Incus container running Debian. The network configuration is managed using Netplan to ensure proper network integration.
+
+\section{Prerequisites}
+Before proceeding, ensure the following:
+\begin{itemize}
+  \item Incus is installed on the host system (\texttt{sudo apt install incus}).
+  \item A Debian-based container is created in Incus.
+  \item Basic knowledge of Linux networking and container management.
+  \item Root or sudo access to the host and container.
+\end{itemize}
+
+\section{Step-by-Step Configuration}
+
+\subsection{Creating and Setting Up the Incus Container}
+% Creating the Incus container
+Create a Debian container named \texttt{dnsmasq-container} using the following command on the host:
+\begin{lstlisting}[language=bash]
+incus create images:debian/12 dnsmasq-container
+incus config set dnsmasq-container security.syscalls.intercept.mount true
+incus start dnsmasq-container
+\end{lstlisting}
+The \texttt{security.syscalls.intercept.mount} setting is required for \texttt{dnsmasq} to function correctly in the container.
+
+% Accessing the container
+Access the container:
+\begin{lstlisting}[language=bash]
+incus exec dnsmasq-container -- bash
+\end{lstlisting}
+
+\subsection{Installing dnsmasq}
+% Installing dnsmasq and dependencies
+Update the package list and install \texttt{dnsmasq}:
+\begin{lstlisting}[language=bash]
+apt update
+apt install dnsmasq -y
+\end{lstlisting}
+
+\subsection{Configuring the Network with Netplan}
+% Setting up the network interface
+Configure the container's network using Netplan to assign a static IP address. Edit the Netplan configuration file (e.g., \texttt{/etc/netplan/01-netcfg.yaml}):
+\begin{lstlisting}[language=bash]
+nano /etc/netplan/01-netcfg.yaml
+\end{lstlisting}
+Add the following configuration:
+\begin{lstlisting}[language=yaml]
+network:
+  version: 2
+  ethernets:
+    eth0:
+      dhcp4: no
+      addresses:
+        - 192.168.1.10/24
+      gateway4: 192.168.1.1
+      nameservers:
+        addresses: [8.8.8.8, 8.8.4.4]
+\end{lstlisting}
+Apply the configuration:
+\begin{lstlisting}[language=bash]
+netplan apply
+\end{lstlisting}
+
+\subsection{Configuring dnsmasq}
+% Configuring dnsmasq for DNS and DHCP
+Edit the \texttt{dnsmasq} configuration file at \texttt{/etc/dnsmasq.conf}:
+\begin{lstlisting}[language=bash]
+nano /etc/dnsmasq.conf
+\end{lstlisting}
+Add or modify the following settings to enable DNS and DHCP:
+\begin{lstlisting}
+# DNS settings
+domain-needed
+bogus-priv
+no-resolv
+server=8.8.8.8
+server=8.8.4.4
+local=/example.local/
+domain=example.local
+
+# DHCP settings
+dhcp-range=192.168.1.100,192.168.1.200,12h
+dhcp-option=3,192.168.1.1
+dhcp-option=6,8.8.8.8,8.8.4.4
+\end{lstlisting}
+
+\textbf{Explanation:}
+\begin{itemize}
+  \item \texttt{domain-needed}: Prevents incomplete domain names from being sent to upstream DNS.
+  \item \texttt{bogus-priv}: Blocks reverse DNS lookups for private IP ranges.
+  \item \texttt{no-resolv}: Disables reading \texttt{/etc/resolv.conf}.
+  \item \texttt{server}: Specifies upstream DNS servers (Google DNS in this case).
+  \item \texttt{local} and \texttt{domain}: Configures a local domain.
+  \item \texttt{dhcp-range}: Defines the IP range for DHCP clients (from 192.168.1.100 to 192.168.1.200, lease time 12 hours).
+  \item \texttt{dhcp-option}: Sets the default gateway (option 3) and DNS servers (option 6).
+\end{itemize}
+
+\subsection{Starting and Enabling dnsmasq}
+% Starting the dnsmasq service
+Restart the \texttt{dnsmasq} service to apply the configuration:
+\begin{lstlisting}[language=bash]
+systemctl restart dnsmasq
+systemctl enable dnsmasq
+\end{lstlisting}
+Verify that \texttt{dnsmasq} is running:
+\begin{lstlisting}[language=bash]
+systemctl status dnsmasq
+\end{lstlisting}
+
+\subsection{Testing the Configuration}
+% Testing DNS and DHCP
+Test the DNS resolution from within the container:
+\begin{lstlisting}[language=bash]
+nslookup example.local 192.168.1.10
+\end{lstlisting}
+To test DHCP, connect a client device to the same network and verify that it receives an IP address in the range \texttt{192.168.1.100--192.168.1.200}.
+
+\section{Troubleshooting}
+If \texttt{dnsmasq} fails to start:
+\begin{itemize}
+  \item Check the logs: \texttt{journalctl -u dnsmasq}.
+  \item Ensure no other service is using port 53 (DNS) or 67 (DHCP).
+  \item Verify the network configuration with \texttt{ip a} and \texttt{ping 8.8.8.8}.
+\end{itemize}
+
+\section{Conclusion}
+This guide configures \texttt{dnsmasq} as a DNS and DHCP server in an Incus container on Debian. The Netplan configuration ensures proper network setup. For advanced configurations, refer to the \texttt{dnsmasq} documentation (\texttt{man dnsmasq}).
+
+\end{document}

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