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\usepackage{seqsplit}           % Splits long words.
%\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
%\usepackage[english,german,french,spanish,italian]{babel}              % Languages

% Document Info
\author{Tekgenius}
\pdfinfo{
  /Title (itec-2210.pdf)
  /Creator (Cheatography)
  /Author (Tekgenius)
  /Subject (ITEC 2210 Cheat Sheet)
}

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% Commands
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% Header and Footer
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\fancyhead[L]{
\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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\columnbreak
\begin{tabulary}{11cm}{L}
    \vspace{-2pt}\large{\bf{\textcolor{DarkBackground}{\textrm{ITEC 2210 Cheat Sheet}}}} \\
    \normalsize{by \textcolor{DarkBackground}{Tekgenius} via \textcolor{DarkBackground}{\uline{cheatography.com/97395/cs/20888/}}}
\end{tabulary}
\end{multicols}}

\fancyfoot[L]{ \footnotesize
\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{LL}
  \SetRowColor{FootBackground}
  \mymulticolumn{2}{p{5.377cm}}{\bf\textcolor{white}{Cheatographer}}  \\
  \vspace{-2pt}Tekgenius \\
  \uline{cheatography.com/tekgenius} \\
  \end{tabulary}
\vfill
\columnbreak
\begin{tabulary}{5.8cm}{L}
  \SetRowColor{FootBackground}
  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Cheat Sheet}}  \\
   \vspace{-2pt}Published 23rd October, 2019.\\
   Updated 23rd October, 2019.\\
   Page {\thepage} of \pageref{LastPage}.
\end{tabulary}
\vfill
\columnbreak
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  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Sponsor}}  \\
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  \vspace{-5pt}
  %\includegraphics[width=48px,height=48px]{dave.jpeg}
  Measure your website readability!\\
  www.readability-score.com
\end{tabulary}
\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}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Troubleshooting}}  \tn
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{1.Find out what the problem is, which should have EAR(expected, actual, reproduction) \newline % Row Count 2 (+ 2)
2.Triage the Situation, make sure the system is still in as good of a condition under the circumstances. \newline % Row Count 5 (+ 3)
3.Examine as best you can inc. Logs. \newline % Row Count 6 (+ 1)
4.Diagnose problem using elimination, successive refinement, bisection. You can use elimination, bisection, or successive refinement. \newline % Row Count 9 (+ 3)
5/6. Test the changes and "Cure"(Deploy)% Row Count 10 (+ 1)
} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{TCP/IP}}  \tn
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{4 Layer System: \newline % Row Count 1 (+ 1)
Application Layer(Like Youtube) \newline % Row Count 2 (+ 1)
TCP(Transport Layer): Wants to know how it's going to get to it's location(also makes it a packet at that point) \newline % Row Count 5 (+ 3)
Internet (IP) Layer: Uses IP addresses to send the packets through a network interface to an IP(Which works like a house address) \newline % Row Count 8 (+ 3)
Network Interface: This is how a packet get's transferred(Ie. Wifi, Ethernet, Etc.)  \newline % Row Count 10 (+ 2)
TCP Handshake: (A \textgreater{} B) SYN, (B \textgreater{} A) ACK-SYN, (A \textgreater{} B) SYN. \newline % Row Count 12 (+ 2)
UDP is stateless and has minimal overhead, packet has addressing and data with dupe protection. \newline % Row Count 14 (+ 2)
Vlans are their own networks, to traverse VLANs% Row Count 15 (+ 1)
} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Launching a Service}}  \tn
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{1. Define the ready list by Must have features, would be nice features, bugs and regressions, assertions and approvals. \newline % Row Count 3 (+ 3)
2. Work on the ready list \newline % Row Count 4 (+ 1)
3. Launch the beta with staging \seqsplit{environments(dev-QA-UAT-beta-prod)} \newline % Row Count 6 (+ 2)
4.Launch production \newline % Row Count 7 (+ 1)
5.Capture Lessons by making sure mistakes won't be repeated again. \newline % Row Count 9 (+ 2)
6.Repeat% Row Count 10 (+ 1)
} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Linux Commands}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{cat - concatenate files and print the standard output \newline id - prints real and effective user and group IDs \newline sudo- executes commands as a root user \newline adduser - add a user or group to the system \newline ctlr+l - clear terminal \newline ls - list the directory \newline touch - changes the file timestamps \newline chown - change the file owner and group \newline chgrp - change the group ownership \newline chmod - change file access permissions \newline apt-get/apt- get packages/install applications \newline tree- like ls but listing the content of directories \newline ln- make a symbolic link between files \newline dig- performs dns lookups \newline host - resolve a hostname into a IP address \newline whois - tells you who owns the ip/hostname} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
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\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Containers and VM's}}  \tn
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{Types: \newline % Row Count 1 (+ 1)
IAS(Infrastructure as a Service), Vendor gives Infras, you do everything else on your own \newline % Row Count 3 (+ 2)
PAS(Platform as a Service), run an application using framework or environment specific to a vendor \newline % Row Count 5 (+ 2)
SAS(Software as a Service) basically Youtube/Github.  \newline % Row Count 7 (+ 2)
VM's: \newline % Row Count 8 (+ 1)
HVM(Needs to pause VM to use hardware such as a sata controller) \newline % Row Count 10 (+ 2)
PV(Paravirtualization) just sends the I/O calls directly to the VMM. \newline % Row Count 12 (+ 2)
Containers: \newline % Row Count 13 (+ 1)
Basically VM's but with no set resources.% Row Count 14 (+ 1)
} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
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\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
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\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Networking}}  \tn
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{RING Topology \newline % Row Count 1 (+ 1)
It is called ring topology because it forms a ring as each computer is connected to another computer, with the last one connected to the first. Exactly two neighbours for each device. \newline % Row Count 5 (+ 4)
STAR Topology \newline % Row Count 6 (+ 1)
In this type of topology all the computers are connected to a single hub through a cable. This hub is the central node and all others nodes are connected to the central node. \newline % Row Count 10 (+ 4)
TREE Topology \newline % Row Count 11 (+ 1)
It has a root node and all other nodes are connected to it forming a hierarchy. For example if in an office in one department ring topology is used and in another star topology is used, connecting these topologies will result in Hybrid Topology (ring topology and star topology).% Row Count 17 (+ 6)
} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}


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

\end{document}