Transcript Introduction

CIT 470: Advanced Network and
System Administration
Documentation
CIT 470: Advanced Network and System Administration
Slide #1
Topics
1.
2.
3.
4.
Why document
How to document
External documentation
Man pages
CIT 470: Advanced Network and System Administration
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Why Document
Teaches SAs how to do critical procedures
– So you can go on vacation.
– So you can get promoted.
Self-help desk
– Let users solve their problems quickly.
– Requires less time from SAs.
CIT 470: Advanced Network and System Administration
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Forms of Documentation
Text files and web pages
– Generic free form text, READMEs, etc.
Man pages
– UNIX manual pages for commands, configs, etc.
FAQs
– Frequently asked question lists.
Reference Lists
– Vendors w/ contact info, serial numbers, employee dir
Checklists and HOWTOs
– Step by step description of a procedure.
– Ex: new hire, installs, OS hardening
CIT 470: Advanced Network and System Administration
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Documentation Template
Title:
– Simple, short description.
Metadata:
– Author with contact information
– Revision date, history
What:
– Description of what the document tells you to do.
How
– Step by step description of procedure.
– Indicate why you’re doing steps where appropriate.
CIT 470: Advanced Network and System Administration
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Sources for Documentation
Command history
– Use script command before starting.
– Use history command after finishing.
Screen shots
– Print screen
– import command to grab windows.
Email
– Email conversations may describe commands.
– Don’t use as documentation; just as a source.
Request Tickets
– Problem solutions often documented in notes.
CIT 470: Advanced Network and System Administration
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Documentation Storage
Shared directory
– README to describe rules and policies.
– Subdirectories for topics.
– Text or HTML files in directories.
Web site
– Directory shared via web server.
Content Management System
– Web-based publishing and collaboration tool.
– Provides access control, versioning, easy markup.
CIT 470: Advanced Network and System Administration
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Wiki
Collaborative web-editing software.
– Invented by Ward Cunningham in 1995.
– Wiki is a Hawaiian word for fast.
Features
–
–
–
–
Edit pages within web browser.
Simplified markup language.
Version control of pages.
Access control limits who can read and/or edit.
CIT 470: Advanced Network and System Administration
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Version Control
• Allows tracking
of history of
changes.
• Can compare
different
versions.
• Can revert to
older versions
in case of bad
edits or spam.
CIT 470: Advanced Network and System Administration
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Search
Text-based storage
– grep can search any text files.
– Indexing programs can provide faster searches for large
repositories of text or binary data.
Binary storage
– Binary document formats, like those used by word procs,
are much harder to search.
– Often restricted to using creator application’s search
capabilities.
Web search programs can be installed for web.
– Spider program crawls site to build index.
– Search program accesses index to find search terms.
CIT 470: Advanced Network and System Administration
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Off-site Links
Use off-site links to provide documentation.
– Many references, howtos, FAQs outside org.
Use anonymizing redirection
– HTTP Referer header will reveal URL from
internal site, which may leak project and people
names and other information.
CIT 470: Advanced Network and System Administration
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External Documentation
tldp.org: The Linux Documentation Project
–
–
–
–
Man pages
FAQs
HOWTOs
Guides (online books)
howtoforge.com: Many Linux HOWTOs
– Mostly OS + server install and configuration.
ugu.com: UNIX Guru Universe
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Man pages
Standard online UNIX documentation.
– Commands
– Configuration files
– Programming interfaces
Accessible
– man pagename
– man section pagename
– Web-based man pages.
Searchable
– man –k keyword
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Man sections
1.
2.
3.
4.
5.
6.
7.
8.
User commands that anyone can use.
System calls (kernel functions.)
Library functions for programmers.
Devices (hardware interfaces in /dev)
File format descriptions (/etc/passwd)
Game, graphics demos.
Miscellaneous (boot, icmp, url, man-pages)
System administration tools for root.
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whichman
Find matching man pages in all sections.
– Helps find which section you need.
– Uses fuzzy matching algorithm.
$ whichman -0 printf
/usr/share/man/man1/printf.1.gz
/usr/share/man/man3/printf.3.gz
$ whichman printf
/usr/share/man/man1/printafm.1.gz
/usr/share/man/man1/printf.1.gz
/usr/share/man/man1/print.1.gz
/usr/share/man/man3/print.3ncurses.gz
/usr/share/man/man3/snprintf.3.gz
/usr/share/man/man3/vdprintf.3.gz
/usr/share/man/man3/vsprintf.3.gz
/usr/share/man/man3/vfprintf.3.gz
/usr/share/man/man3/wprintf.3.gz
CIT 470: Advanced Network and System Administration
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Man Page Storage
Stored under /usr/share/man
– Subdirectories for each section.
– May include language-specific subdirectories.
– MANPATH environment variable is a :-separated
list of paths to search for man pages.
Man page files
– Often compressed with gzip.
– File suffix is a number indicating the section.
– Written in nroff text-formatting language.
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Man Page Output
LS(1)
User Commands
LS(1)
NAME
ls - list directory contents
SYNOPSIS
ls [OPTION]... [FILE]...
DESCRIPTION
List information about the FILEs (the current directory by default).
Sort entries alphabetically if none of -cftuvSUX nor --sort.
Mandatory arguments to long options are
too.
mandatory
for
short
options
-a, --all
do not ignore entries starting with .
-A, --almost-all
do not list implied . and ..
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nroff code for page
.TH LS "1" "June 2006" "ls 5.97" "User Commands"
.SH NAME
ls \- list directory contents
.SH SYNOPSIS
.B ls
[\fIOPTION\fR]... [\fIFILE\fR]...
.SH DESCRIPTION
.\" Add any additional description here
.PP
List information about the FILEs (the current directory by default).
Sort entries alphabetically if none of \fB\-cftuvSUX\fR nor \fB\-\sort\fR.
.PP
Mandatory arguments to long options are mandatory for short options too.
.TP
\fB\-a\fR, \fB\-\-all\fR
do not ignore entries starting with .
.TP
\fB\-A\fR, \fB\-\-almost\-all\fR
do not list implied . and ..
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nroff codes
Title Header: .TH prog mansect cf lf ch
Sections: .SH sectionname
– NAME is required.
– Most have: SYNOPSIS, DECRIPTION, OPTIONS, FILES, BUGS,
AUTHOR, SEE ALSO
Paragraphs
–
–
–
–
.PP: new paragraph
.TP: index text that comes 2 lines after this macro
.NF: pre-formatted text
.”: comment line
Fonts
– .B: bold (also \fB)
– .I: italics (also \fI)
– .R: roman (also \fR)
CIT 470: Advanced Network and System Administration
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References
1. Mark Burgess, Principles of Network and System
Administration, 2nd edition, Wiley, 2004.
2. Aeleen Frisch, Essential System Administration,
3rd edition, O’Reilly, 2002.
3. Thomas A. Limoncelli and Christine Hogan, The
Practice of System and Network Administration,
2nd edition, Addison-Wesley, 2007.
4. Evi Nemeth et al, UNIX System Administration
Handbook, 3rd edition, Prentice Hall, 2001.
CIT 470: Advanced Network and System Administration
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