I'd like to start a collection of good, free cheat sheet resources for system administrators. Please add your favorite ones. From the Wikipedia "cheat sheet" article:

In more general usage, a "cheat sheet" is any short (one or two page) reference to terms, commands, or symbols where the user is expected to understand the use of such terms etc but not necessarily to have memorized all of them.

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44 Answers 44

I add my own favorite: Cheat Sheets on PacketLife.com has some very nice ones on network technology topics.

Cheat sheets are in PDF format. You are welcome to use and redistribute them as you please, so long as they remain intact and unmodified.

Currently there are six categories:

  • Protocols: BGP, EIGRP, First Hop Redundancy, IEEE 802.11 Wireless, IEEE 802.1X, IPsec, IPv4 Multicast, IPv6, IS-IS, OSPF, Spanning Tree
  • Applications: tcpdump, Wireshark Display Filters
  • Reference: Common Ports, IP Access Lists, Subnetting
  • Syntax: Markdown, MediaWiki
  • Technologies: MPLS, Quality of Service, VLANs
  • Miscellaneous: Cisco IOS Versions, Physical Terminations

Examples: Common Ports and IPv6 (links to PDF files)

Common Ports Cheat Sheet (PDF)

  • 6
    Oh, so THAT site is why wget has a --mirror function... Thanks! – Matt Simmons Jun 25 '09 at 19:25
  • 2
    You know you have all that info in /etc/services, right Ok no color but still, it's handy – niXar Jun 26 '09 at 7:39

I wish to use this at some point... for now though, I'm a nano dork but thought it might be handy for some here:

Printable (PDFs)

QWERTY:http://locobox.googlepages.com/vi-vim-cheat-sheet-qwerty.pdf Dvorak:http://locobox.googlepages.com/vi-vim-cheat-sheet-dvorak.pdf

alt text http://locobox.googlepages.com/vi-vim-cheat-sheet.gif

  • Nice, thanks for the contribution! – splattne Jun 25 '09 at 15:53
  • a little frightened to ask, but do you have the qwerty? – Notmyfault Jun 25 '09 at 23:41
  • The link is to the DVORAK but the image posted is for the QWERTY – Mark Henderson Jun 26 '09 at 4:17
  • Sorry about that... ok, I added a link for the QWERTY version (now, both are there). Thanks for letting me know. – l0c0b0x Jun 26 '09 at 5:05
  • Hm. I think i prefer not to have to use a cheat sheet for my text editor. – RCIX Nov 19 '09 at 9:37

Map of the internet

Source

  • 3
    I wonder what that looks like today. – Martijn Heemels Jun 25 '09 at 21:51
  • That's pretty cool! – Saif Khan Jun 27 '09 at 14:32
  • @Martijn Heemels: As of Feb 2011, it's much less interesting - no more green squares, IPv4 fully allocated. – Piskvor Feb 8 '11 at 15:15
  • I love the ~~~ wavey lines! – Alan Aug 4 '11 at 14:09

Protocol encapsulation chart from Wildpackets (PDF format)

Protocol encapsulation chart image

Just my 2 cents.

  • rlogin and rsh but no ssh? What is this, 1993? – Teddy Feb 1 '10 at 14:19

Google.com (I know - it's not a list with two-word commands, but it saves my behind every time).

  • 2
    had to give it a +1 – cop1152 Jun 25 '09 at 12:55

Computer Hardware Chart (Geekologie):

Hardware Chart

Nice Windows 2008 technology posters available here:

Windows Server 2008 Component Posters

  • Windows Server 2008 Feature Components
  • Windows Server 2008 Active Directory Components

These two posters, originally published in the July 2007 issue of TechNet Magazine, provide a strong visual tool to aide in the understanding of various features and components of Windows Server 2008. One poster focuses exclusively on powerful new Active Directory technologies, while the other provides a technical look at a variety of new features available in Windows Server 2008 (such as Server Core, Network Access Protection, and more).

Windows Server 2008 PDF Posters

And a list with cheat sheets for different languages, systems and so on.

http://www.cheat-sheets.org/

  • Am I happy to find this link! – Mister IT Guru Jan 28 '11 at 13:31

SQL Server Cheat Sheet

The SQL Server cheat sheet is a one-page A4 printable document, designed to provide a quick reference for SQL Server. A description of what is on the cheat sheet follows, or if you are impatient, you can go straight to the full size SQL Server cheat sheet.

  • Data Types and Conversion
  • Functions
  • Creations

SQL Server Data Types and Conversion

Download link: PDF file

Windows 2003 Command Line Reference is more of a 50 lb manual than a cheat sheet, though if someone has something lightweight with the compressed syntax, that would rock...

Not free, but definitely worth mentioning.
xkcd have a wearable Linux cheat sheet.

xkcd Linux cheat shirt

Life's cheat sheet http://909sickle.com/s/lifes-cheat-sheet/lifes-cheat-sheet.png

Source

  • 8
    your math doesn't add up here. you are born -1000 then going the job route you get +1000. Unless I missed something or this is some new age math stuff I thought -1000 + 1000 = 0. And then you get taxed on the 1000 that you earned so you really have -1. Am I missing something. – TechGuyTJ Jun 25 '09 at 12:39
  • 1
    I think you'll have to ask the author about this... Don't shoot the messenger ;-) – fretje Jun 25 '09 at 12:47
  • 4
    -1 (to the author) for spelling "marriage" incorrectly. – Dennis Williamson Jun 25 '09 at 21:31

System Administrator Interview Cheat Sheet

  • Wow, this is a great resource! Thank you. – splattne Jul 6 '09 at 15:28

Simple RAID Cheat Sheet

I'm sure it's just because I don't mess with RAID that often, but when I do need it, this is immensely helpful.

  • The right link is: hyperionreactor.net/content/simple-raid-cheat-sheet – splattne Jun 25 '09 at 12:19
  • I edited the answer with the correct link. – splattne Jun 25 '09 at 12:20
  • It misses RAID-6, which is more and more common. And RAID-4, found in NetApp, DataDirect Networks and some other high-end products. – wazoox Jun 25 '09 at 16:07
  • If you've got a cheat sheet that has those, I'll add it into my post. – phuzion Jun 25 '09 at 16:50
  • The link appears to be broken again. – Zoredache Oct 13 '09 at 21:30

Unix Toolbox

This document is a collection of Unix/Linux/BSD commands and tasks which are useful for IT work or for advanced users. This is a practical guide with concise explanations, however the reader is supposed to know what s/he is doing.

  • very nice! Thanks! – l0c0b0x Jun 7 '10 at 23:17

http://www.connectionstrings.com

I use it all the time for system administrator and developer related tasks, especially when trying to make an applications talk to a database other than what it was originally designed for and the support isn't all that great.

  • Oh yes, I also use it when I have to deal with some exotic databases. Like Access ;-) – splattne Jul 7 '09 at 13:50
  • Heh. Yeah, all my Access work is done out of pity. – squillman Jul 7 '09 at 14:29

As an admin (and after) I find that I need to often create tools for the browser.

I'm not a designer (nor do I desire to be one), but I have found VisiBone cheat sheets immensely helpful:

I created a Vim cheatsheet in various formats a couple of years ago: Vim Cheatsheet

Found this whimpy list of links to various sheets for various technologies...there's only, oh, I dunno, three dozen of these...

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