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% Most of the following are not required for the majority
% of cheat sheets but are needed for some symbol support.
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% Document Info
\author{Bayan (Bayan.A)}
\pdfinfo{
  /Title (centos-systems-administration-and-security.pdf)
  /Creator (Cheatography)
  /Author (Bayan (Bayan.A))
  /Subject (CentOS - Systems Administration and Security 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{CentOS - Systems Administration and Security Cheat Sheet}}}} \\
    \normalsize{by \textcolor{DarkBackground}{Bayan (Bayan.A)} via \textcolor{DarkBackground}{\uline{cheatography.com/122738/cs/44041/}}}
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\fancyfoot[L]{ \footnotesize
\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{LL}
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  \mymulticolumn{2}{p{5.377cm}}{\bf\textcolor{white}{Cheatographer}}  \\
  \vspace{-2pt}Bayan (Bayan.A) \\
  \uline{cheatography.com/bayan-a} \\
  \end{tabulary}
\vfill
\columnbreak
\begin{tabulary}{5.8cm}{L}
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  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Cheat Sheet}}  \\
   \vspace{-2pt}Published 6th August, 2024.\\
   Updated 6th August, 2024.\\
   Page {\thepage} of \pageref{LastPage}.
\end{tabulary}
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  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Sponsor}}  \\
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  %\includegraphics[width=48px,height=48px]{dave.jpeg}
  Measure your website readability!\\
  www.readability-score.com
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\begin{document}
\raggedright
\raggedcolumns

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


\begin{tabularx}{17.67cm}{x{7.5988 cm} x{9.6712 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{17.67cm}}{\bf\textcolor{white}{Install Apache / Verify Status}}  \tn
% Row 0
\SetRowColor{LightBackground}
{\bf{Install HTTPD service}} & `yum install httpd` \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
{\bf{Check httpd status}} & `systemctl status httpd.service` \tn 
% Row Count 4 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{17.67cm}{x{7.4261 cm} x{9.8439 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{17.67cm}}{\bf\textcolor{white}{Confirguring Apache HTTP Server}}  \tn
% Row 0
\SetRowColor{LightBackground}
{\bf{Inspect Control Script}} & `less \seqsplit{/etc/systemd/system/multi-user}.target.wants/httpd.service` \tn 
% Row Count 3 (+ 3)
% Row 1
\SetRowColor{white}
 & displays the contents of the httpd.service file for the Apache HTTP server in the systemd multi-user target. \tn 
% Row Count 8 (+ 5)
% Row 2
\SetRowColor{LightBackground}
{\bf{Get default start-up state}} & `systemctl get-default` \tn 
% Row Count 10 (+ 2)
% Row 3
\SetRowColor{white}
 & shows the default target (runlevel) that the system boots into. \tn 
% Row Count 13 (+ 3)
% Row 4
\SetRowColor{LightBackground}
{\bf{Find config file}} & `find / -name httpd.conf ` \tn 
% Row Count 15 (+ 2)
% Row 5
\SetRowColor{white}
{\bf{Inspect config file}} & `nano \seqsplit{/etc/httpd/conf/httpd.conf`} \tn 
% Row Count 17 (+ 2)
% Row 6
\SetRowColor{LightBackground}
 & nano {[}location of config file found using `find`{]} \tn 
% Row Count 20 (+ 3)
% Row 7
\SetRowColor{white}
{\bf{`.htaccess \& .htpasswd`}} & Note that these are hidden by default, to prevent files being viewed by web clients \tn 
% Row Count 24 (+ 4)
% Row 8
\SetRowColor{LightBackground}
{\bf{`ErrorLog`}} & Find and take note of where the errorlog is located (usually `logs/error\_log`) \tn 
% Row Count 28 (+ 4)
% Row 9
\SetRowColor{white}
{\bf{`DocumentRoot`}} & The web document location is usually the `/var/www/html` \tn 
% Row Count 31 (+ 3)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{17.67cm}{x{9.1531 cm} x{8.1169 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{17.67cm}}{\bf\textcolor{white}{Investigate Processes, Make \& Test Apache}}  \tn
% Row 0
\SetRowColor{LightBackground}
{\bf{List processes and filters for those related to httpd}} & `ps -ef $\frac{3}{4}$ grep httpd` \tn 
% Row Count 3 (+ 3)
% Row 1
\SetRowColor{white}
{\bf{Rules for incoming traffic}} & `iptables -L INPUT` \tn 
% Row Count 5 (+ 2)
% Row 2
\SetRowColor{LightBackground}
{\bf{Create index.html file}} & 1) Navigate to appropriate directory \tn 
% Row Count 7 (+ 2)
% Row 3
\SetRowColor{white}
 & e.g.: `cd /var/www/html` \tn 
% Row Count 9 (+ 2)
% Row 4
\SetRowColor{LightBackground}
 & 2) create and edit file using nano \tn 
% Row Count 11 (+ 2)
% Row 5
\SetRowColor{white}
 & e.g.: `sudo nano index.html` \tn 
% Row Count 13 (+ 2)
% Row 6
\SetRowColor{LightBackground}
{\bf{View access log}} & `cat \seqsplit{/var/log/httpd/access\_log`} \tn 
% Row Count 15 (+ 2)
% Row 7
\SetRowColor{white}
{\bf{Request local page}} & ` curl http:/localhost ` \tn 
% Row Count 17 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{17.67cm}{x{8.635 cm} x{8.635 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{17.67cm}}{\bf\textcolor{white}{MySQL/MariaDB Installation, Start \& Status}}  \tn
% Row 0
\SetRowColor{LightBackground}
{\bf{MariaDB Installation}} & `yum install mariadb-server` \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
{\bf{Confirm MySQL/MariaDB is installed}} & `find / -name mysql` \tn 
% Row Count 4 (+ 2)
% Row 2
\SetRowColor{LightBackground}
{\bf{Start MariaDB}} & `systemctl start mariadb` \tn 
% Row Count 6 (+ 2)
% Row 3
\SetRowColor{white}
{\bf{Check MariaDB Status}} & `systemctl status mariadb` \tn 
% Row Count 8 (+ 2)
% Row 4
\SetRowColor{LightBackground}
{\bf{Confirm servers are running}} & `ps -ef` \tn 
% Row Count 10 (+ 2)
% Row 5
\SetRowColor{white}
 & This produces a list of running servers, where you will search for `mysql` in the far left column(the UID(User ID)) \tn 
% Row Count 16 (+ 6)
% Row 6
\SetRowColor{LightBackground}
{\bf{Set new password for mysqladmin root}} & `mysqladmin -u root password {[}INSERT PASSWORD{]}` \tn 
% Row Count 19 (+ 3)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{17.67cm}{x{8.4623 cm} x{8.8077 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{17.67cm}}{\bf\textcolor{white}{MySQL Config file \& Data Directory}}  \tn
% Row 0
\SetRowColor{LightBackground}
{\bf{Find config file (my.cnf) location}} & `sudo find / -name my.cnf $\frac{3}{4}$ less` \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
{\bf{Navigate to config file directory}} & `cd {[}INSERT DIRECTORY{]}` \tn 
% Row Count 4 (+ 2)
% Row 2
\SetRowColor{LightBackground}
 & e.g. in my case, my.cnf was located found to be /etc/my.cnf, so `cd /etc` is used \tn 
% Row Count 9 (+ 5)
% Row 3
\SetRowColor{white}
{\bf{View contents of config file}} & `cat my.cnf` \tn 
% Row Count 11 (+ 2)
% Row 4
\SetRowColor{LightBackground}
{\bf{Locate MySQL Daemon}} & `find / -name {\emph{mysqld}}` \tn 
% Row Count 13 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{17.67cm}{x{8.635 cm} x{8.635 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{17.67cm}}{\bf\textcolor{white}{Create \& Populate Database}}  \tn
% Row 0
\SetRowColor{LightBackground}
{\bf{Enter MariaDB Server}} & `mysql -h localhost -u root -p` \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
 & Then enter password created previously. Note, password will not show any typing. \tn 
% Row Count 6 (+ 4)
% Row 2
\SetRowColor{LightBackground}
{\bf{Create database}} & `CREATE DATABASE {[}database name{]}; \tn 
% Row Count 8 (+ 2)
% Row 3
\SetRowColor{white}
 & e.g. `CREATE DATABASE food;` \tn 
% Row Count 10 (+ 2)
% Row 4
\SetRowColor{LightBackground}
{\bf{Change to created database}} & `USE {[}database{]}` \tn 
% Row Count 12 (+ 2)
% Row 5
\SetRowColor{white}
 & e.g. `USE food' \tn 
% Row Count 13 (+ 1)
% Row 6
\SetRowColor{LightBackground}
{\bf{Exit MariaDB}} & `quit` \tn 
% Row Count 14 (+ 1)
% Row 7
\SetRowColor{white}
{\bf{Confirm database was created outside of MariaDB}} & Change to appropriate directory `cd /var/lib/mysql` \tn 
% Row Count 17 (+ 3)
% Row 8
\SetRowColor{LightBackground}
 & Display contents of current directory using `ls` \tn 
% Row Count 20 (+ 3)
% Row 9
\SetRowColor{white}
{\bf{Create Table}} & `CREATE TABLE restaurant (name VARCHAR(40), type VARCHAR(40), location VARCHAR(4));`` \tn 
% Row Count 25 (+ 5)
% Row 10
\SetRowColor{LightBackground}
 & VARCHAR(n) defines variable length \tn 
% Row Count 27 (+ 2)
% Row 11
\SetRowColor{white}
{\bf{Insert values into restaurant table}} & `INSERT INTO restaurant (name, type, location) values ("Pizzahut", "Italian", "SW10");` \tn 
% Row Count 32 (+ 5)
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{17.67cm}{x{8.635 cm} x{8.635 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{17.67cm}}{\bf\textcolor{white}{Create \& Populate Database (cont)}}  \tn
% Row 12
\SetRowColor{LightBackground}
{\bf{Show table}} & `SHOW TABLES; DESCRIBE restaurant; SELECT * FROM restaurant;` \tn 
% Row Count 4 (+ 4)
% Row 13
\SetRowColor{white}
{\bf{Delete value from table}} & `DELETE FROM restaurant WHERE \seqsplit{name="Pizza"\&\&location="SW10";`} \tn 
% Row Count 8 (+ 4)
% Row 14
\SetRowColor{LightBackground}
{\bf{Create new user}} & `GRANT SELECT ON food.restaurant TO bayan@localhost IDENTIFIED BY \seqsplit{"bayans\_password";`} \tn 
% Row Count 13 (+ 5)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{17.67cm}{x{8.635 cm} x{8.635 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{17.67cm}}{\bf\textcolor{white}{Firewalls}}  \tn
% Row 0
\SetRowColor{LightBackground}
{\bf{Confirm firewalld is running}} & `systemctl status firewalld` \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
{\bf{Check firewall conifiguration}} & `firewall-cmd -{}-list-all` \tn 
% Row Count 4 (+ 2)
% Row 2
\SetRowColor{LightBackground}
{\bf{Display firewall rules}} & `iptables -L' \tn 
% Row Count 6 (+ 2)
% Row 3
\SetRowColor{white}
{\bf{Services/ports available for sshd}} & `systemctl status sshd` \tn 
% Row Count 8 (+ 2)
% Row 4
\SetRowColor{LightBackground}
{\bf{Services/ports available for httpd}} & `systemctl status httpd` \tn 
% Row Count 10 (+ 2)
% Row 5
\SetRowColor{white}
{\bf{Services/ports available for vsftp}} & `systemctl status vsftp` \tn 
% Row Count 12 (+ 2)
% Row 6
\SetRowColor{LightBackground}
 & if not installed, use yum install. e.g. `yum install vsftpd` \tn 
% Row Count 15 (+ 3)
% Row 7
\SetRowColor{white}
{\bf{Stop firewalld, then check if running to confirm it is infact stopped}}** & `systemctl stop firewalld` \tn 
% Row Count 19 (+ 4)
% Row 8
\SetRowColor{LightBackground}
{\bf{Start firewalld}} & `systemctl start firewalld` \tn 
% Row Count 21 (+ 2)
% Row 9
\SetRowColor{white}
{\bf{Add http service to firewall configuration}} & `firewall-cmd -{}-add-service http` \tn 
% Row Count 24 (+ 3)
% Row 10
\SetRowColor{LightBackground}
{\bf{Add ftp service to firewall configuration}} & `firewall-cmd -{}-add-service ftp` \tn 
% Row Count 27 (+ 3)
% Row 11
\SetRowColor{white}
{\bf{iptables rules for accepting traffic for ports 22(SSH), 80(HTTP), and 21 (FTP)}} & `iptables -A INPUT -p tcp -{}-dport 22 -j ACCEPT` \tn 
% Row Count 32 (+ 5)
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{17.67cm}{x{8.635 cm} x{8.635 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{17.67cm}}{\bf\textcolor{white}{Firewalls (cont)}}  \tn
% Row 12
\SetRowColor{LightBackground}
 & `iptables -A INPUT -p tcp -{}-dport 80 -j ACCEPT` \tn 
% Row Count 3 (+ 3)
% Row 13
\SetRowColor{white}
 & `iptables -A INPUT -p tcp -{}-dport 21 -j ACCEPT` \tn 
% Row Count 6 (+ 3)
% Row 14
\SetRowColor{LightBackground}
{\bf{Add rules to output chain}} & `iptables  -A OUTPUT -m state -{}-state ESTABLISHED, RELATED -j ACCEPT` \tn 
% Row Count 10 (+ 4)
% Row 15
\SetRowColor{white}
{\bf{Dropping default rules for INPUT and OUTPUT traffic}} & `iptables -P INPUT DROP` \tn 
% Row Count 13 (+ 3)
% Row 16
\SetRowColor{LightBackground}
 & `iptables -P OUTPUT DROP` \tn 
% Row Count 15 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{17.67cm}{x{8.635 cm} x{8.635 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{17.67cm}}{\bf\textcolor{white}{SELinux}}  \tn
% Row 0
\SetRowColor{LightBackground}
{\bf{Install setroubleshoot and httpd}} & `sudo yum install setroubleshoot httpd` \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
{\bf{Enable httpd}} & `systemctl enable httpd` \tn 
% Row Count 4 (+ 2)
% Row 2
\SetRowColor{LightBackground}
{\bf{Start httpd}} & `systemctl start httpd` \tn 
% Row Count 6 (+ 2)
% Row 3
\SetRowColor{white}
{\bf{Check default directory for HTML files}} & `cat \seqsplit{/etc/httpdconf/httpd}.conf | grep DocumentRoot` \tn 
% Row Count 9 (+ 3)
% Row 4
\SetRowColor{LightBackground}
{\bf{Check SELinux permissions / context}} & `ls -lZ index.html` \tn 
% Row Count 11 (+ 2)
% Row 5
\SetRowColor{white}
{\bf{Temporarily disable SELinux enforcement for troubleshooting or testing without changing the permanent configuration.}} & `setenforce 0` \tn 
% Row Count 17 (+ 6)
% Row 6
\SetRowColor{LightBackground}
{\bf{Re-enable SELinux enforcement after it has been disabled, restoring its security policies.}} & `setenforce 1` \tn 
% Row Count 22 (+ 5)
% Row 7
\SetRowColor{white}
{\bf{Apply default SELinux to  a file:}} & `/sbin/restorecon -v \seqsplit{/var/www/html/secret}.html` \tn 
% Row Count 25 (+ 3)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}



\end{document}