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%\usepackage{opensans}          % Can't make this work so far. Shame. Would be lovely.
\usepackage[normalem]{ulem}     % For underlining links
% Most of the following are not required for the majority
% of cheat sheets but are needed for some symbol support.
\usepackage{amsmath}            % Symbols
\usepackage{MnSymbol}           % Symbols
\usepackage{wasysym}            % Symbols
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% Document Info
\author{cyphox90}
\pdfinfo{
  /Title (rhel-command-list.pdf)
  /Creator (Cheatography)
  /Author (cyphox90)
  /Subject (RHEL command list Cheat Sheet)
}

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\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{C}
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    \vspace{-7pt}
    {\parbox{\dimexpr\textwidth-2\fboxsep\relax}{\noindent
        \hspace*{-6pt}\includegraphics[width=5.8cm]{/web/www.cheatography.com/public/images/cheatography_logo.pdf}}
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\begin{tabulary}{11cm}{L}
    \vspace{-2pt}\large{\bf{\textcolor{DarkBackground}{\textrm{RHEL command list Cheat Sheet}}}} \\
    \normalsize{by \textcolor{DarkBackground}{cyphox90} via \textcolor{DarkBackground}{\uline{cheatography.com/192992/cs/40221/}}}
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\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{LL}
  \SetRowColor{FootBackground}
  \mymulticolumn{2}{p{5.377cm}}{\bf\textcolor{white}{Cheatographer}}  \\
  \vspace{-2pt}cyphox90 \\
  \uline{cheatography.com/cyphox90} \\
  \end{tabulary}
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\begin{tabulary}{5.8cm}{L}
  \SetRowColor{FootBackground}
  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Cheat Sheet}}  \\
   \vspace{-2pt}Not Yet Published.\\
   Updated 9th September, 2023.\\
   Page {\thepage} of \pageref{LastPage}.
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  \vspace{-5pt}
  %\includegraphics[width=48px,height=48px]{dave.jpeg}
  Measure your website readability!\\
  www.readability-score.com
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\end{multicols}}




\begin{document}
\raggedright
\raggedcolumns

% Set font size to small. Switch to any value
% from this page to resize cheat sheet text:
% www.emerson.emory.edu/services/latex/latex_169.html
\footnotesize % Small font.

\begin{multicols*}{3}

\begin{tabularx}{5.377cm}{x{3.13551 cm} x{1.84149 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Version, Kernel \& Package details}}  \tn
% Row 0
\SetRowColor{LightBackground}
Verify RHEL installed version & cat \seqsplit{/etc/redhat-release} \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
Verify RHEL has the correct version of SLES installed. Log in as root user. & cat \seqsplit{/etc/SuSE-release} \tn 
% Row Count 5 (+ 3)
% Row 2
\SetRowColor{LightBackground}
Display the RHEL kernel version & uname-r \tn 
% Row Count 7 (+ 2)
% Row 3
\SetRowColor{white}
Display the RHEL kernel version & uname -mrs \tn 
% Row Count 9 (+ 2)
% Row 4
\SetRowColor{LightBackground}
Display the RHEL kernel version & uname -a \tn 
% Row Count 11 (+ 2)
% Row 5
\SetRowColor{white}
List all packages with RPM & rpm -{}-query -{}-all \tn 
% Row Count 13 (+ 2)
% Row 6
\SetRowColor{LightBackground}
List all installed RPM packages & rpm -qa \tn 
% Row Count 15 (+ 2)
% Row 7
\SetRowColor{white}
List all installed YUM packages & yum list installed \tn 
% Row Count 17 (+ 2)
% Row 8
\SetRowColor{LightBackground}
List all installed DNF packages & dnf list installed \tn 
% Row Count 19 (+ 2)
% Row 9
\SetRowColor{white}
View current firewall settings & \seqsplit{firewall-config} \tn 
% Row Count 21 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{x{2.43873 cm} x{2.53827 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Notes for SSH}}  \tn
% Row 0
\SetRowColor{LightBackground}
Use SSH Public Key based login & \textasciitilde{} \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
Disable root user login & add users to a SUDO group \tn 
% Row Count 4 (+ 2)
% Row 2
\SetRowColor{LightBackground}
Disable password based login & \seqsplit{AuthenticationMethods} publickey \seqsplit{PubkeyAuthentication} yes \tn 
% Row Count 7 (+ 3)
% Row 3
\SetRowColor{white}
Limit users SSH access & AllowUsers first lastname \tn 
% Row Count 9 (+ 2)
% Row 4
\SetRowColor{LightBackground}
Disable empty passwords & \seqsplit{PermitEmptyPasswords} no \tn 
% Row Count 11 (+ 2)
% Row 5
\SetRowColor{white}
Firewall SSH TCP port \#22 & \textasciitilde{} \tn 
% Row Count 13 (+ 2)
% Row 6
\SetRowColor{LightBackground}
Configure idle log out timeout interval & ClientAliveInterval 300 ClientAliveCountMax 0 \tn 
% Row Count 16 (+ 3)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{x{2.4885 cm} x{2.4885 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{RHEL firewalld}}  \tn
% Row 0
\SetRowColor{LightBackground}
View the current status of firewalld & firewall-cmd -{}-state or systemctl status firewalld \tn 
% Row Count 3 (+ 3)
% Row 1
\SetRowColor{white}
View current firewalld settings in window & firewall-config \tn 
% Row Count 6 (+ 3)
% Row 2
\SetRowColor{LightBackground}
View current firewalld settings via CLI & firewall-cmd -{}-list-all \tn 
% Row Count 8 (+ 2)
% Row 3
\SetRowColor{white}
View what services are allowed in the current firewalld zone & firewall-cmd -{}-list-services \tn 
% Row Count 11 (+ 3)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{x{2.4885 cm} x{2.4885 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{SSH \& Hostnamectl identification}}  \tn
% Row 0
\SetRowColor{LightBackground}
Identify Port number in OpenSSH server config file & grep Port \seqsplit{/etc/ssh/sshd\_config} \tn 
% Row Count 3 (+ 3)
% Row 1
\SetRowColor{white}
Identify Port number in OpenSSH client config file & grep Port \seqsplit{/etc/ssh/ssh\_config} \tn 
% Row Count 6 (+ 3)
% Row 2
\SetRowColor{LightBackground}
Identify system wide OpenSSH config file for client & cat \seqsplit{/etc/ssh\_ssh\_config} \tn 
% Row Count 9 (+ 3)
% Row 3
\SetRowColor{white}
View all hostnamectl & hostnamectl status \tn 
% Row Count 10 (+ 1)
% Row 4
\SetRowColor{LightBackground}
Confirm SSH password authentication & grep sshd -T | grep \seqsplit{PasswordAuthentication} \tn 
% Row Count 13 (+ 3)
% Row 5
\SetRowColor{white}
Find all failed SSH login attempts & grep "Failed password" /var/log/auth.log \tn 
% Row Count 15 (+ 2)
% Row 6
\SetRowColor{LightBackground}
Find all failed SSH login attempts & cat /var/log/auth.log | grep "Failed password \tn 
% Row Count 18 (+ 3)
% Row 7
\SetRowColor{white}
List all IP adddresses that attempted login \& failed & grep "Failed password" /var/log/auth.log | awk '\{print \$11\}' | uniq -c | sort -nr \tn 
% Row Count 23 (+ 5)
% Row 8
\SetRowColor{LightBackground}
(1) Finding failed SSH login attempts & grep "authentication failure" /var/log/secure \tn 
% Row Count 26 (+ 3)
% Row 9
\SetRowColor{white}
(1) Finding failed SSH login attempts & grep -E -i 'authentication failure|Invalid user' /var/log/secure | grep sshd \tn 
% Row Count 30 (+ 4)
\end{tabularx}
\par\addvspace{1.3em}

\vfill
\columnbreak
\begin{tabularx}{5.377cm}{x{2.4885 cm} x{2.4885 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{SSH \& Hostnamectl identification (cont)}}  \tn
% Row 10
\SetRowColor{LightBackground}
(1) Finding failed SSH login attempts & grep -E \seqsplit{'sshd.*Failed|Invalid|Did|failure'} /var/log/secure \tn 
% Row Count 3 (+ 3)
% Row 11
\SetRowColor{white}
(1) Finding failed SSH login attempts & grep -E \seqsplit{'sshd.*Failed|Invalid|Did|failure'} /var/log/auth.log \tn 
% Row Count 6 (+ 3)
% Row 12
\SetRowColor{LightBackground}
(2) Finding failed SSH login attempts (awk print statement may need to be changed) & grep "authentication failure" /var/log/secure | awk '\{ print \$13 \}' | cut -b7-  | sort | uniq -c \tn 
% Row Count 11 (+ 5)
% Row 13
\SetRowColor{white}
Testing SUDO access & sudo -i \tn 
% Row Count 12 (+ 1)
% Row 14
\SetRowColor{LightBackground}
Identify sudoers with authorisation & cat /etc/sudoers \tn 
% Row Count 14 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{x{3.13551 cm} x{1.84149 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Basic SELinux settings}}  \tn
% Row 0
\SetRowColor{LightBackground}
Display current SELinux state mode & getenforce \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
Check SELlinux SELINUX variable to persist across rebots & cat \seqsplit{/etc/selinux/config} \tn 
% Row Count 5 (+ 3)
% Row 2
\SetRowColor{LightBackground}
Identify if NTP is installed & chkconfig -{}-list ntpd \tn 
% Row Count 7 (+ 2)
% Row 3
\SetRowColor{white}
Identify if ntpd is running & ntpq -p \tn 
% Row Count 9 (+ 2)
% Row 4
\SetRowColor{LightBackground}
Check NTP sync status & timedatectl \tn 
% Row Count 10 (+ 1)
% Row 5
\SetRowColor{white}
Check NTP sync status & timedatectl status \tn 
% Row Count 12 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}


% That's all folks
\end{multicols*}

\end{document}