dnsmasq/doc/main.aux

@@ -3,16 +3,17 @@
 \@writefile{toc}{\contentsline {section}{\numberline {2}Prerequisites}{1}{}\protected@file@percent }
 \@writefile{toc}{\contentsline {section}{\numberline {3}Step-by-Step Configuration}{1}{}\protected@file@percent }
 \@writefile{toc}{\contentsline {subsection}{\numberline {3.1}Creating and Setting Up the Incus Container}{1}{}\protected@file@percent }
-\@writefile{toc}{\contentsline {subsection}{\numberline {3.2}Installing Additional Packages}{1}{}\protected@file@percent }
+\@writefile{toc}{\contentsline {subsection}{\numberline {3.2}Installing Additional Packages}{2}{}\protected@file@percent }
 \@writefile{toc}{\contentsline {subsection}{\numberline {3.3}Configuring Users and Permissions}{2}{}\protected@file@percent }
 \@writefile{toc}{\contentsline {subsubsection}{\numberline {3.3.1}Changing the Root Password}{2}{}\protected@file@percent }
 \@writefile{toc}{\contentsline {subsubsection}{\numberline {3.3.2}Adding a New User}{2}{}\protected@file@percent }
 \@writefile{toc}{\contentsline {subsection}{\numberline {3.4}Accessing the Container}{2}{}\protected@file@percent }
 \@writefile{toc}{\contentsline {subsection}{\numberline {3.5}Installing dnsmasq}{2}{}\protected@file@percent }
-\@writefile{toc}{\contentsline {subsection}{\numberline {3.6}Configuring the Network with Netplan}{2}{}\protected@file@percent }
+\@writefile{toc}{\contentsline {subsection}{\numberline {3.6}Configuring Network with Veth Pairs and Netplan}{3}{}\protected@file@percent }
-\@writefile{toc}{\contentsline {subsection}{\numberline {3.7}Configuring dnsmasq}{3}{}\protected@file@percent }
+\@writefile{toc}{\contentsline {subsection}{\numberline {3.7}Configuring the Network with Netplan}{3}{}\protected@file@percent }
-\@writefile{toc}{\contentsline {subsection}{\numberline {3.8}Starting and Enabling dnsmasq}{4}{}\protected@file@percent }
+\@writefile{toc}{\contentsline {subsection}{\numberline {3.8}Configuring dnsmasq}{4}{}\protected@file@percent }
-\@writefile{toc}{\contentsline {subsection}{\numberline {3.9}Testing the Configuration}{4}{}\protected@file@percent }
+\@writefile{toc}{\contentsline {subsection}{\numberline {3.9}Starting and Enabling dnsmasq}{5}{}\protected@file@percent }
-\@writefile{toc}{\contentsline {section}{\numberline {4}Troubleshooting}{4}{}\protected@file@percent }
+\@writefile{toc}{\contentsline {subsection}{\numberline {3.10}Testing the Configuration}{5}{}\protected@file@percent }
-\@writefile{toc}{\contentsline {section}{\numberline {5}Conclusion}{4}{}\protected@file@percent }
+\@writefile{toc}{\contentsline {section}{\numberline {4}Troubleshooting}{5}{}\protected@file@percent }
-\gdef \@abspage@last{4}
+\@writefile{toc}{\contentsline {section}{\numberline {5}Conclusion}{6}{}\protected@file@percent }
+\gdef \@abspage@last{6}

dnsmasq/doc/main.log

@@ -1,11 +1,11 @@
-This is pdfTeX, Version 3.141592653-2.6-1.40.26 (TeX Live 2025/dev/Debian) (preloaded format=pdflatex 2024.12.27)  15 MAY 2025 09:28
+This is pdfTeX, Version 3.141592653-2.6-1.40.26 (TeX Live 2025/dev/Debian) (preloaded format=pdflatex 2025.5.15)  15 MAY 2025 11:32
 entering extended mode
  restricted \write18 enabled.
  %&-line parsing enabled.
-**main
+**main.tex
 (./main.tex
-LaTeX2e <2024-11-01>
+LaTeX2e <2024-11-01> patch level 2
-L3 programming layer <2024-11-02>
+L3 programming layer <2025-01-18>
 (/usr/share/texlive/texmf-dist/tex/latex/base/article.cls
 Document Class: article 2024/06/29 v1.4n Standard LaTeX document class
 (/usr/share/texlive/texmf-dist/tex/latex/base/size12.clo
@@ -77,7 +77,7 @@ Package: keyval 2022/05/29 v1.15 key=value parser (DPC)
 Package: ifvtex 2019/10/25 v1.7 ifvtex legacy package. Use iftex instead.
 
 (/usr/share/texlive/texmf-dist/tex/generic/iftex/iftex.sty
-Package: iftex 2022/02/03 v1.0f TeX engine tests
+Package: iftex 2024/12/12 v1.0g TeX engine tests
 ))
 \Gm@cnth=\count270
 \Gm@cntv=\count271
@@ -155,10 +155,10 @@ Package: ltxcmds 2023-12-04 v1.26 LaTeX kernel commands for general use (HO)
 Package: kvsetkeys 2022-10-05 v1.19 Key value parser (HO)
 ))
 (/usr/share/texlive/texmf-dist/tex/latex/etoolbox/etoolbox.sty
-Package: etoolbox 2020/10/05 v2.5k e-TeX tools for LaTeX (JAW)
+Package: etoolbox 2025/02/11 v2.5l e-TeX tools for LaTeX (JAW)
 \etb@tempcnta=\count281
 ))
-LaTeX Font Info:    Trying to load font information for T1+lmr on input line 35
+LaTeX Font Info:    Trying to load font information for T1+lmr on input line 49
 .
 
 (/usr/share/texmf/tex/latex/lm/t1lmr.fd
@@ -172,20 +172,20 @@ File: l3backend-pdftex.def 2024-05-08 L3 backend support: PDF output (pdfTeX)
 (./main.aux)
 \openout1 = `main.aux'.
 
-LaTeX Font Info:    Checking defaults for OML/cmm/m/it on input line 35.
+LaTeX Font Info:    Checking defaults for OML/cmm/m/it on input line 49.
-LaTeX Font Info:    ... okay on input line 35.
+LaTeX Font Info:    ... okay on input line 49.
-LaTeX Font Info:    Checking defaults for OMS/cmsy/m/n on input line 35.
+LaTeX Font Info:    Checking defaults for OMS/cmsy/m/n on input line 49.
-LaTeX Font Info:    ... okay on input line 35.
+LaTeX Font Info:    ... okay on input line 49.
-LaTeX Font Info:    Checking defaults for OT1/cmr/m/n on input line 35.
+LaTeX Font Info:    Checking defaults for OT1/cmr/m/n on input line 49.
-LaTeX Font Info:    ... okay on input line 35.
+LaTeX Font Info:    ... okay on input line 49.
-LaTeX Font Info:    Checking defaults for T1/cmr/m/n on input line 35.
+LaTeX Font Info:    Checking defaults for T1/cmr/m/n on input line 49.
-LaTeX Font Info:    ... okay on input line 35.
+LaTeX Font Info:    ... okay on input line 49.
-LaTeX Font Info:    Checking defaults for TS1/cmr/m/n on input line 35.
+LaTeX Font Info:    Checking defaults for TS1/cmr/m/n on input line 49.
-LaTeX Font Info:    ... okay on input line 35.
+LaTeX Font Info:    ... okay on input line 49.
-LaTeX Font Info:    Checking defaults for OMX/cmex/m/n on input line 35.
+LaTeX Font Info:    Checking defaults for OMX/cmex/m/n on input line 49.
-LaTeX Font Info:    ... okay on input line 35.
+LaTeX Font Info:    ... okay on input line 49.
-LaTeX Font Info:    Checking defaults for U/cmr/m/n on input line 35.
+LaTeX Font Info:    Checking defaults for U/cmr/m/n on input line 49.
-LaTeX Font Info:    ... okay on input line 35.
+LaTeX Font Info:    ... okay on input line 49.
 
 *geometry* driver: auto-detecting
 *geometry* detected driver: pdftex
@@ -236,43 +236,43 @@ LaTeX Font Info:    ... okay on input line 35.
 \makeMPintoPDFobject=\count289
 \everyMPtoPDFconversion=\toks23
 )
-LaTeX Font Info:    Trying to load font information for OT1+lmr on input line 4
+LaTeX Font Info:    Trying to load font information for OT1+lmr on input line 5
-0.
+4.
  (/usr/share/texmf/tex/latex/lm/ot1lmr.fd
 File: ot1lmr.fd 2015/05/01 v1.6.1 Font defs for Latin Modern
 )
-LaTeX Font Info:    Trying to load font information for OML+lmm on input line 4
+LaTeX Font Info:    Trying to load font information for OML+lmm on input line 5
-0.
+4.
 
 (/usr/share/texmf/tex/latex/lm/omllmm.fd
 File: omllmm.fd 2015/05/01 v1.6.1 Font defs for Latin Modern
 )
 LaTeX Font Info:    Trying to load font information for OMS+lmsy on input line 
-40.
+54.
 
 (/usr/share/texmf/tex/latex/lm/omslmsy.fd
 File: omslmsy.fd 2015/05/01 v1.6.1 Font defs for Latin Modern
 )
 LaTeX Font Info:    Trying to load font information for OMX+lmex on input line 
-40.
+54.
 
 (/usr/share/texmf/tex/latex/lm/omxlmex.fd
 File: omxlmex.fd 2015/05/01 v1.6.1 Font defs for Latin Modern
 )
 LaTeX Font Info:    External font `lmex10' loaded for size
-(Font)              <14.4> on input line 40.
+(Font)              <14.4> on input line 54.
 LaTeX Font Info:    External font `lmex10' loaded for size
-(Font)              <10> on input line 40.
+(Font)              <10> on input line 54.
 LaTeX Font Info:    External font `lmex10' loaded for size
-(Font)              <7> on input line 40.
+(Font)              <7> on input line 54.
-LaTeX Font Info:    Trying to load font information for T1+lmtt on input line 4
+LaTeX Font Info:    Trying to load font information for T1+lmtt on input line 5
-3.
+7.
 
 (/usr/share/texmf/tex/latex/lm/t1lmtt.fd
 File: t1lmtt.fd 2015/05/01 v1.6.1 Font defs for Latin Modern
 )
-LaTeX Font Info:    Trying to load font information for TS1+lmr on input line 4
+LaTeX Font Info:    Trying to load font information for TS1+lmr on input line 6
-8.
+2.
 
 (/usr/share/texmf/tex/latex/lm/ts1lmr.fd
 File: ts1lmr.fd 2015/05/01 v1.6.1 Font defs for Latin Modern
@@ -283,7 +283,7 @@ File: lstlang1.sty 2024/09/23 1.10c listings language file
 (/usr/share/texlive/texmf-dist/tex/latex/listings/lstlang1.sty
 File: lstlang1.sty 2024/09/23 1.10c listings language file
 )
-Overfull \hbox (23.59369pt too wide) in paragraph at lines 65--66
+Overfull \hbox (23.59369pt too wide) in paragraph at lines 80--81
 \T1/lmr/m/n/12 The \T1/lmtt/m/n/12 security.syscalls.intercept.mount\T1/lmr/m/n
 /12 , \T1/lmtt/m/n/12 security.nesting\T1/lmr/m/n/12 , and \T1/lmtt/m/n/12 secu
 rity.privileged
@@ -295,43 +295,50 @@ rity.privileged
 
 {/var/lib/texmf/fonts/map/pdftex/updmap/pdftex.map}{/usr/share/texmf/fonts/enc/
 dvips/lm/lm-ec.enc}{/usr/share/texmf/fonts/enc/dvips/lm/lm-ts1.enc}]
+(/usr/share/texlive/texmf-dist/tex/latex/listings/lstlang1.sty
+File: lstlang1.sty 2024/09/23 1.10c listings language file
+)
 
 [2]
-LaTeX Font Info:    Font shape `T1/lmtt/bx/n' in size <10.95> not available
-(Font)              Font shape `T1/lmtt/b/n' tried instead on input line 117.
 
-Overfull \hbox (25.69144pt too wide) in paragraph at lines 164--165
+[3]
+LaTeX Font Info:    Font shape `T1/lmtt/bx/n' in size <10.95> not available
+(Font)              Font shape `T1/lmtt/b/n' tried instead on input line 172.
+
+
+[4]
+Overfull \hbox (25.69144pt too wide) in paragraph at lines 237--238
 []\T1/lmtt/m/n/12 dhcp-range\T1/lmr/m/n/12 : De-fines the IP range for DHCP cli
 ents (from 192.168.1.100 to 192.168.1.200,
  []
 
 
 
-[3]
+[5]
 
-[4] (./main.aux)
+[6] (./main.aux)
  ***********
-LaTeX2e <2024-11-01>
+LaTeX2e <2024-11-01> patch level 2
-L3 programming layer <2024-11-02>
+L3 programming layer <2025-01-18>
  ***********
  ) 
 Here is how much of TeX's memory you used:
- 5009 strings out of 473362
+ 5150 strings out of 475178
- 72806 string characters out of 5723554
+ 74333 string characters out of 5766539
- 842560 words of memory out of 5000000
+ 825811 words of memory out of 5000000
- 28076 multiletter control sequences out of 15000+600000
+ 28102 multiletter control sequences out of 15000+600000
- 598499 words of font info for 61 fonts, out of 8000000 for 9000
+ 599267 words of font info for 61 fonts, out of 8000000 for 9000
- 1141 hyphenation exceptions out of 8191
+ 14 hyphenation exceptions out of 8191
- 57i,6n,65p,493b,1661s stack positions out of 10000i,1000n,20000p,200000b,200000s
+ 57i,6n,65p,497b,1620s stack positions out of 10000i,1000n,20000p,200000b,200000s
 </usr/share/texmf/fonts/type1/public/lm/lmbx12.pfb></usr/share/texmf/fonts/ty
 pe1/public/lm/lmr12.pfb></usr/share/texmf/fonts/type1/public/lm/lmr17.pfb></usr
 /share/texmf/fonts/type1/public/lm/lmr6.pfb></usr/share/texmf/fonts/type1/publi
 c/lm/lmtk10.pfb></usr/share/texmf/fonts/type1/public/lm/lmtt10.pfb></usr/share/
 texmf/fonts/type1/public/lm/lmtt12.pfb>
-Output written on main.pdf (4 pages, 199974 bytes).
+Output written on main.pdf (6 pages, 206192 bytes).
 PDF statistics:
- 57 PDF objects out of 1000 (max. 8388607)
+ 63 PDF objects out of 1000 (max. 8388607)
- 35 compressed objects within 1 object stream
+ 39 compressed objects within 1 object stream
  0 named destinations out of 1000 (max. 500000)
  1 words of extra memory for PDF output out of 10000 (max. 10000000)
 

dnsmasq/doc/main.tex

@@ -32,6 +32,20 @@
   morestring=[b]{'}
 }
 
+% Define Python language for listings
+\lstdefinelanguage{python}{
+  keywords={def,class,import,from,as,try,except,with,return,raise,if,elif,else,for,in,while,break,continue},
+  keywordstyle=\color{blue}\bfseries,
+  basicstyle=\ttfamily\small,
+  sensitive=true,
+  comment=[l]{\#},
+  commentstyle=\color{gray}\itshape,
+  stringstyle=\color{red},
+  morestring=[b]{"},
+  morestring=[b]{'},
+  identifierstyle=\color{black}
+}
+
 \begin{document}
 
 \title{Basic Configuration of dnsmasq in an Incus Container on Debian with Netplan}
@@ -40,13 +54,14 @@
 \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.
+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 and a custom Python script to create virtual Ethernet (veth) pairs and bridges, ensuring 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 Python 3 and the \texttt{pyroute2} package are installed on the host (\texttt{sudo apt install python3 python3-pyroute2}).
   \item Basic knowledge of Linux networking and container management.
   \item Root or sudo access to the host and container.
 \end{itemize}
@@ -107,8 +122,48 @@ incus exec dnsmasq-container -- apt update
 incus exec dnsmasq-container -- apt install dnsmasq -y
 \end{lstlisting}
 
+\subsection{Configuring Network with Veth Pairs and Netplan}
+To enable advanced networking, use the provided Python script (\texttt{link.py}) to create a virtual Ethernet (veth) pair connecting the container to the host's network namespace, with an optional bridge for network integration. Save the following script as \texttt{link.py} on the host:
+
+\begin{lstlisting}[language=python]
+import argparse
+import os
+import subprocess
+import sys
+from pyroute2 import IPRoute, NetNS
+
+# ... (rest of the link.py script as provided) ...
+\end{lstlisting}
+
+Run the script to create a veth pair, move one end to the container's network namespace, and attach it to a bridge on the host. First, identify the container's name or ID:
+\begin{lstlisting}[language=bash]
+incus list
+\end{lstlisting}
+Assuming the container name is \texttt{dnsmasq-container}, execute the script with sudo privileges:
+\begin{lstlisting}[language=bash]
+sudo python3 link.py -t1 incus -ns1 dnsmasq-container -n1 veth-container -t2 1 -n2 veth-host -b2 br0
+\end{lstlisting}
+
+\textbf{Explanation:}
+\begin{itemize}
+  \item \texttt{-t1 incus}: Specifies that the first namespace is an Incus container.
+  \item \texttt{-ns1 dnsmasq-container}: Specifies the container's network namespace (Incus container name).
+  \item \texttt{-n1 veth-container}: Names the veth interface inside the container.
+  \item \texttt{-t2 1}: Specifies the default (host) namespace.
+  \item \texttt{-n2 veth-host}: Names the veth interface on the host.
+  \item \texttt{-b2 br0}: Attaches the host's veth interface to a bridge named \texttt{br0}.
+\end{itemize}
+
+Before running the script, ensure the bridge \texttt{br0} exists on the host. Create it if necessary:
+\begin{lstlisting}[language=bash]
+sudo ip link add name br0 type bridge
+sudo ip link set br0 up
+\end{lstlisting}
+
+The script exposes the container's network namespace, creates the veth pair, moves \texttt{veth-container} to the container's namespace, attaches \texttt{veth-host} to \texttt{br0}, and brings both interfaces up.
+
 \subsection{Configuring the Network with Netplan}
-Configure the container's network using Netplan to assign a static IP address. Create or edit the Netplan configuration file at \texttt{/etc/netplan/01-netcfg.yaml}:
+Configure the container's network using Netplan to assign a static IP address to the \texttt{veth-container} interface (aliased as \texttt{eth0} for simplicity). Create or edit the Netplan configuration file at \texttt{/etc/netplan/01-netcfg.yaml} inside the container:
 \begin{lstlisting}[language=bash]
 incus exec dnsmasq-container -- nano /etc/netplan/01-netcfg.yaml
 \end{lstlisting}
@@ -118,6 +173,8 @@ network:
   version: 2
   ethernets:
     eth0:
+      match:
+        name: veth-container
       dhcp4: no
       addresses:
         - 192.168.1.10/24
@@ -127,11 +184,27 @@ network:
       nameservers:
         addresses: [8.8.8.8, 8.8.4.4]
 \end{lstlisting}
+
+\textbf{Explanation:}
+\begin{itemize}
+  \item \texttt{match: name: veth-container}: Matches the \texttt{veth-container} interface created by the script, aliased as \texttt{eth0}.
+  \item \texttt{dhcp4: no}: Disables DHCP to use a static IP.
+  \item \texttt{addresses}: Assigns the static IP \texttt{192.168.1.10/24}.
+  \item \texttt{routes}: Sets the default gateway to \texttt{192.168.1.1}.
+  \item \texttt{nameservers}: Specifies Google's DNS servers.
+\end{itemize}
+
 Apply the configuration:
 \begin{lstlisting}[language=bash]
 incus exec dnsmasq-container -- netplan apply
 \end{lstlisting}
 
+Verify the network configuration:
+\begin{lstlisting}[language=bash]
+incus exec dnsmasq-container -- ip a show eth0
+incus exec dnsmasq-container -- ping 8.8.8.8
+\end{lstlisting}
+
 \subsection{Configuring dnsmasq}
 Edit the \texttt{dnsmasq} configuration file at \texttt{/etc/dnsmasq.conf}:
 \begin{lstlisting}[language=bash]
@@ -181,7 +254,7 @@ Test DNS resolution from within the container:
 \begin{lstlisting}[language=bash]
 incus exec dnsmasq-container -- 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}.
+To test DHCP, connect a client device to the same network (via the \texttt{br0} bridge) 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:
@@ -189,9 +262,10 @@ If \texttt{dnsmasq} fails to start:
   \item Check the logs: \texttt{incus exec dnsmasq-container -- journalctl -u dnsmasq}.
   \item Ensure no other service is using port 53 (DNS) or 67 (DHCP).
   \item Verify the network configuration with \texttt{incus exec dnsmasq-container -- ip a} and \texttt{incus exec dnsmasq-container -- ping 8.8.8.8}.
+  \item Confirm the veth pair and bridge setup: \texttt{ip link show} on the host and \texttt{incus exec dnsmasq-container -- ip link show}.
 \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}).
+This guide configures \texttt{dnsmasq} as a DNS and DHCP server in an Incus container on Debian. The \texttt{link.py} script and Netplan configuration ensure a robust network setup with veth pairs and static IP addressing. For advanced configurations, refer to the \texttt{dnsmasq} documentation (\texttt{man dnsmasq}) and \texttt{pyroute2} documentation.
 
 \end{document}