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https://github.com/monitoring-plugins/monitoring-plugins.git
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git-svn-id: https://nagiosplug.svn.sourceforge.net/svnroot/nagiosplug/nagiosplug/trunk@38 f882894a-f735-0410-b71e-b25c423dba1c
931 lines
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19 KiB
HTML
931 lines
No EOL
19 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN">
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<HTML
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><HEAD
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><TITLE
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>Nagios plug-in development guidelines</TITLE
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><META
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NAME="GENERATOR"
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CONTENT="Modular DocBook HTML Stylesheet Version 1.64
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"></HEAD
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><BODY
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CLASS="BOOK"
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BGCOLOR="#FFFFFF"
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TEXT="#000000"
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VLINK="#840084"
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ALINK="#0000FF"
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><DIV
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CLASS="BOOK"
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><A
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NAME="AEN1"
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></A
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><DIV
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CLASS="TITLEPAGE"
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><H1
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CLASS="TITLE"
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><A
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NAME="AEN3"
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>Nagios plug-in development guidelines</A
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></H1
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><H3
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CLASS="AUTHOR"
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><A
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NAME="AEN5"
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>Karl DeBisschop</A
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></H3
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><DIV
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CLASS="AFFILIATION"
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><DIV
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CLASS="ADDRESS"
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><P
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CLASS="ADDRESS"
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>karl@debisschop.net</P
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></DIV
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></DIV
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><H3
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CLASS="AUTHOR"
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><A
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NAME="AEN11"
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>Ethan Galstad</A
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></H3
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><DIV
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CLASS="AFFILIATION"
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><DIV
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CLASS="ADDRESS"
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><P
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CLASS="ADDRESS"
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>netsaint@linuxbox.com</P
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></DIV
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></DIV
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><H3
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CLASS="AUTHOR"
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><A
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NAME="AEN21"
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>Hugo Gayosso</A
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></H3
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><DIV
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CLASS="AFFILIATION"
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><DIV
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CLASS="ADDRESS"
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><P
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CLASS="ADDRESS"
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>hgayosso@gnu.org</P
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></DIV
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></DIV
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><H3
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CLASS="AUTHOR"
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><A
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NAME="AEN27"
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>Subhendu Ghosh</A
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></H3
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><DIV
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CLASS="AFFILIATION"
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><DIV
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CLASS="ADDRESS"
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><P
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CLASS="ADDRESS"
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>sghosh@sourceforge.net</P
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></DIV
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></DIV
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><H3
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CLASS="AUTHOR"
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><A
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NAME="AEN33"
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>Stanley Hopcroft</A
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></H3
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><DIV
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CLASS="AFFILIATION"
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><DIV
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CLASS="ADDRESS"
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><P
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CLASS="ADDRESS"
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>stanleyhopcroft@sourceforge.net</P
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></DIV
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></DIV
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><P
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CLASS="COPYRIGHT"
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>Copyright © 2000 2001 2002 by Karl DeBisschop, Ethan Galstad,
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Hugo Gayosso, Stanley Hopcroft, Subhendu Ghosh</P
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><HR></DIV
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><DIV
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CLASS="TOC"
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><DL
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><DT
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><B
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>Table of Contents</B
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></DT
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><DT
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><A
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HREF="#PREFACE"
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>About the guidelines</A
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></DT
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><DD
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><DL
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><DT
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><A
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HREF="#AEN51"
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>Copyright</A
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></DT
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></DL
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></DD
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><DT
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><A
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HREF="#AEN56"
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></A
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></DT
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><DD
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><DL
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><DT
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|
><A
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|
HREF="#PLUGOUTPUT"
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>Plugin Output for Nagios</A
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|
></DT
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|
><DD
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|
><DL
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><DT
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|
><A
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|
HREF="#AEN60"
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>Print only one line of text</A
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|
></DT
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|
><DT
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|
><A
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|
HREF="#AEN63"
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|
>Screen Output</A
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|
></DT
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><DT
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><A
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|
HREF="#AEN67"
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>Return the proper status code</A
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|
></DT
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|
><DT
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|
><A
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|
HREF="#AEN71"
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>Plugin Return Codes</A
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|
></DT
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></DL
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></DD
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|
><DT
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|
><A
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|
HREF="#SYSCMDAUXFILES"
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>System Commands and Auxiliary Files</A
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></DT
|
|
><DD
|
|
><DL
|
|
><DT
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|
><A
|
|
HREF="#AEN117"
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|
>Don't execute system commands without specifying their
|
|
full path</A
|
|
></DT
|
|
><DT
|
|
><A
|
|
HREF="#AEN121"
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|
>Use spopen() if external commands must be executed</A
|
|
></DT
|
|
><DT
|
|
><A
|
|
HREF="#AEN125"
|
|
>Don't make temp files unless absolutely required</A
|
|
></DT
|
|
><DT
|
|
><A
|
|
HREF="#AEN128"
|
|
>Don't be tricked into following symlinks</A
|
|
></DT
|
|
><DT
|
|
><A
|
|
HREF="#AEN131"
|
|
>Validate all input</A
|
|
></DT
|
|
></DL
|
|
></DD
|
|
><DT
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|
><A
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|
HREF="#PERLPLUGIN"
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>Perl Plugins</A
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|
></DT
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><DT
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|
><A
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|
HREF="#RUNTIME"
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|
>Runtime Timeouts</A
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|
></DT
|
|
><DD
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><DL
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><DT
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><A
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|
HREF="#AEN165"
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|
>Use DEFAULT_SOCKET_TIMEOUT</A
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|
></DT
|
|
><DT
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|
><A
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|
HREF="#AEN168"
|
|
>Add alarms to network plugins</A
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|
></DT
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|
></DL
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></DD
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><DT
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><A
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HREF="#PLUGOPTIONS"
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>Plugin Options</A
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></DT
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><DD
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><DL
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><DT
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><A
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|
HREF="#AEN174"
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|
>Option Processing</A
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></DT
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><DT
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><A
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|
HREF="#AEN187"
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>Plugins with more than one type of threshold, or with
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threshold ranges</A
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|
></DT
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></DL
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></DD
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><DT
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><A
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HREF="#SUBMITTINGCHANGES"
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>New submissions and patches</A
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></DT
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></DL
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></DD
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></DL
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></DIV
|
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><DIV
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CLASS="PREFACE"
|
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><HR><H1
|
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><A
|
|
NAME="PREFACE"
|
|
>About the guidelines</A
|
|
></H1
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><P
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>The purpose of this guidelines is to provide a reference for
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the plug-in developers and encourage the standarization of the
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different kind of plug-ins: C, shell, perl, python, etc.</P
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><DIV
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CLASS="SECTION"
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><HR><H1
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|
CLASS="SECTION"
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><A
|
|
NAME="AEN51"
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|
>Copyright</A
|
|
></H1
|
|
><P
|
|
>Nagios Plug-in Development Guidelines Copyright (C) 2000 2001
|
|
2002
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Karl DeBisschop, Ethan Galstad, Hugo Gayosso, Stanley Hopcroft,
|
|
Subhendu Ghosh</P
|
|
><P
|
|
>Permission is granted to make and distribute verbatim
|
|
copies of this manual provided the copyright notice and this
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permission notice are preserved on all copies.</P
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><P
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|
>The plugins themselves are copyrighted by their respective
|
|
authors.</P
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></DIV
|
|
></DIV
|
|
><DIV
|
|
CLASS="ARTICLE"
|
|
><DIV
|
|
CLASS="TOC"
|
|
><DL
|
|
><DT
|
|
><B
|
|
>Table of Contents</B
|
|
></DT
|
|
><DT
|
|
><A
|
|
HREF="#PLUGOUTPUT"
|
|
>Plugin Output for Nagios</A
|
|
></DT
|
|
><DT
|
|
><A
|
|
HREF="#SYSCMDAUXFILES"
|
|
>System Commands and Auxiliary Files</A
|
|
></DT
|
|
><DT
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|
><A
|
|
HREF="#PERLPLUGIN"
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|
>Perl Plugins</A
|
|
></DT
|
|
><DT
|
|
><A
|
|
HREF="#RUNTIME"
|
|
>Runtime Timeouts</A
|
|
></DT
|
|
><DT
|
|
><A
|
|
HREF="#PLUGOPTIONS"
|
|
>Plugin Options</A
|
|
></DT
|
|
><DT
|
|
><A
|
|
HREF="#SUBMITTINGCHANGES"
|
|
>New submissions and patches</A
|
|
></DT
|
|
></DL
|
|
></DIV
|
|
><DIV
|
|
CLASS="SECTION"
|
|
><H1
|
|
CLASS="SECTION"
|
|
><A
|
|
NAME="PLUGOUTPUT"
|
|
>Plugin Output for Nagios</A
|
|
></H1
|
|
><P
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|
>You should always print something to STDOUT that tells if the
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service is working or why its failing. Try to keep the output short -
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probably less that 80 characters. Remember that you ideally would like
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the entire output to appear in a pager message, which will get chopped
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off after a certain length.</P
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|
><DIV
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CLASS="SECTION"
|
|
><HR><H2
|
|
CLASS="SECTION"
|
|
><A
|
|
NAME="AEN60"
|
|
>Print only one line of text</A
|
|
></H2
|
|
><P
|
|
>Nagios will only grab the first line of text from STDOUT
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|
when it notifies contacts about potential problems. If you print
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multiple lines, you're out of luck. Remember, keep it short and
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to the point.</P
|
|
></DIV
|
|
><DIV
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|
CLASS="SECTION"
|
|
><HR><H2
|
|
CLASS="SECTION"
|
|
><A
|
|
NAME="AEN63"
|
|
>Screen Output</A
|
|
></H2
|
|
><P
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|
>The plug-in should print the diagnostic and just the
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|
synopsis part of the help message. A well written plugin would
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|
then have --help as a way to get the verbose help.</P
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|
><P
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|
>Code and output should try to respect the 80x25 size of a
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|
crt (remember when fixing stuff in the server room!)</P
|
|
></DIV
|
|
><DIV
|
|
CLASS="SECTION"
|
|
><HR><H2
|
|
CLASS="SECTION"
|
|
><A
|
|
NAME="AEN67"
|
|
>Return the proper status code</A
|
|
></H2
|
|
><P
|
|
>See <A
|
|
HREF="#RETURNCODES"
|
|
>Table 1 in the section called <I
|
|
>Plugin Return Codes</I
|
|
></A
|
|
> below
|
|
for the numeric values of status codes and their
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|
description. Remember to return an UNKNOWN state if bogus or
|
|
invalid command line arguments are supplied or it you are unable
|
|
to check the service.</P
|
|
></DIV
|
|
><DIV
|
|
CLASS="SECTION"
|
|
><HR><H2
|
|
CLASS="SECTION"
|
|
><A
|
|
NAME="AEN71"
|
|
>Plugin Return Codes</A
|
|
></H2
|
|
><P
|
|
>The return codes below are based on the POSIX spec of returning
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|
a positive value. Netsaint prior to v0.0.7 supported non-POSIX
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|
compliant return code of "-1" for unknown. Nagios supports POSIX return
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|
codes by default.</P
|
|
><P
|
|
>Note: Some plugins will on occasion print on STDOUT that an error
|
|
occurred and error code is 138 or 255 or some such number. These
|
|
are usually caused by plugins using system commands and having not
|
|
enough checks to catch unexpected output. Developers should include a
|
|
default catch-all for system command output that returns an UNKOWN
|
|
return code.</P
|
|
><DIV
|
|
CLASS="TABLE"
|
|
><A
|
|
NAME="RETURNCODES"
|
|
></A
|
|
><P
|
|
><B
|
|
>Table 1. Plugin Return Codes</B
|
|
></P
|
|
><TABLE
|
|
BORDER="1"
|
|
BGCOLOR="#E0E0E0"
|
|
CELLSPACING="0"
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|
CELLPADDING="4"
|
|
CLASS="CALSTABLE"
|
|
><THEAD
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><TR
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><TH
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ALIGN="LEFT"
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VALIGN="TOP"
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|
><P
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|
>Numeric Value</P
|
|
></TH
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|
><TH
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|
ALIGN="LEFT"
|
|
VALIGN="TOP"
|
|
><P
|
|
>Service Status</P
|
|
></TH
|
|
><TH
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|
ALIGN="LEFT"
|
|
VALIGN="TOP"
|
|
><P
|
|
>Status Description</P
|
|
></TH
|
|
></TR
|
|
></THEAD
|
|
><TBODY
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|
><TR
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|
><TD
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|
ALIGN="CENTER"
|
|
VALIGN="TOP"
|
|
><P
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|
>0</P
|
|
></TD
|
|
><TD
|
|
ALIGN="LEFT"
|
|
VALIGN="MIDDLE"
|
|
><P
|
|
>OK</P
|
|
></TD
|
|
><TD
|
|
ALIGN="LEFT"
|
|
VALIGN="TOP"
|
|
><P
|
|
>The plugin was able to check the service and it
|
|
appeared to be functioning properly</P
|
|
></TD
|
|
></TR
|
|
><TR
|
|
><TD
|
|
ALIGN="CENTER"
|
|
VALIGN="TOP"
|
|
><P
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|
>1</P
|
|
></TD
|
|
><TD
|
|
ALIGN="LEFT"
|
|
VALIGN="MIDDLE"
|
|
><P
|
|
>Warning</P
|
|
></TD
|
|
><TD
|
|
ALIGN="LEFT"
|
|
VALIGN="TOP"
|
|
><P
|
|
>The plugin was able to check the service, but it
|
|
appeared to be above some "warning" threshold or did not appear
|
|
to be working properly</P
|
|
></TD
|
|
></TR
|
|
><TR
|
|
><TD
|
|
ALIGN="CENTER"
|
|
VALIGN="TOP"
|
|
><P
|
|
>2</P
|
|
></TD
|
|
><TD
|
|
ALIGN="LEFT"
|
|
VALIGN="MIDDLE"
|
|
><P
|
|
>Critical</P
|
|
></TD
|
|
><TD
|
|
ALIGN="LEFT"
|
|
VALIGN="TOP"
|
|
><P
|
|
>The plugin detected that either the service was not
|
|
running or it was above some "critical" threshold</P
|
|
></TD
|
|
></TR
|
|
><TR
|
|
><TD
|
|
ALIGN="CENTER"
|
|
VALIGN="TOP"
|
|
><P
|
|
>3</P
|
|
></TD
|
|
><TD
|
|
ALIGN="LEFT"
|
|
VALIGN="MIDDLE"
|
|
><P
|
|
>Unknown</P
|
|
></TD
|
|
><TD
|
|
ALIGN="LEFT"
|
|
VALIGN="TOP"
|
|
><P
|
|
>Invalid command line arguments were supplied to the
|
|
plugin or the plugin was unable to check the status of the given
|
|
hosts/service</P
|
|
></TD
|
|
></TR
|
|
></TBODY
|
|
></TABLE
|
|
></DIV
|
|
></DIV
|
|
></DIV
|
|
><DIV
|
|
CLASS="SECTION"
|
|
><HR><H1
|
|
CLASS="SECTION"
|
|
><A
|
|
NAME="SYSCMDAUXFILES"
|
|
>System Commands and Auxiliary Files</A
|
|
></H1
|
|
><DIV
|
|
CLASS="SECTION"
|
|
><H2
|
|
CLASS="SECTION"
|
|
><A
|
|
NAME="AEN117"
|
|
>Don't execute system commands without specifying their
|
|
full path</A
|
|
></H2
|
|
><P
|
|
>Don't use exec(), popen(), etc. to execute external
|
|
commands without explicity using the full path of the external
|
|
program.</P
|
|
><P
|
|
>Doing otherwise makes the plugin vulnerable to hijacking
|
|
by a trojan horse earlier in the search path. See the main
|
|
plugin distribution for examples on how this is done.</P
|
|
></DIV
|
|
><DIV
|
|
CLASS="SECTION"
|
|
><HR><H2
|
|
CLASS="SECTION"
|
|
><A
|
|
NAME="AEN121"
|
|
>Use spopen() if external commands must be executed</A
|
|
></H2
|
|
><P
|
|
>If you have to execute external commands from within your
|
|
plugin and you're writing it in C, use the spopen() function
|
|
that Karl DeBisschop has written.</P
|
|
><P
|
|
>The code for spopen() and spclose() is included with the
|
|
core plugin distribution.</P
|
|
></DIV
|
|
><DIV
|
|
CLASS="SECTION"
|
|
><HR><H2
|
|
CLASS="SECTION"
|
|
><A
|
|
NAME="AEN125"
|
|
>Don't make temp files unless absolutely required</A
|
|
></H2
|
|
><P
|
|
>If temp files are needed, make sure that the plugin will
|
|
fail cleanly if the file can't be written (e.g., too few file
|
|
handles, out of disk space, incorrect permissions, etc.) and
|
|
delete the temp file when processing is complete.</P
|
|
></DIV
|
|
><DIV
|
|
CLASS="SECTION"
|
|
><HR><H2
|
|
CLASS="SECTION"
|
|
><A
|
|
NAME="AEN128"
|
|
>Don't be tricked into following symlinks</A
|
|
></H2
|
|
><P
|
|
>If your plugin opens any files, take steps to ensure that
|
|
you are not following a symlink to another location on the
|
|
system.</P
|
|
></DIV
|
|
><DIV
|
|
CLASS="SECTION"
|
|
><HR><H2
|
|
CLASS="SECTION"
|
|
><A
|
|
NAME="AEN131"
|
|
>Validate all input</A
|
|
></H2
|
|
><P
|
|
>use routines in utils.c or utils.pm and write more as needed</P
|
|
></DIV
|
|
></DIV
|
|
><DIV
|
|
CLASS="SECTION"
|
|
><HR><H1
|
|
CLASS="SECTION"
|
|
><A
|
|
NAME="PERLPLUGIN"
|
|
>Perl Plugins</A
|
|
></H1
|
|
><P
|
|
>Perl plugins are coded a little more defensively than other
|
|
plugins because of embedded Perl. When configured as such, embedded
|
|
Perl Nagios (ePN) requires stricter use of the some of Perl's features.
|
|
This section outlines some of the steps needed to use ePN
|
|
effectively.</P
|
|
><P
|
|
></P
|
|
><OL
|
|
TYPE="1"
|
|
><LI
|
|
><P
|
|
> Do not use BEGIN and END blocks since they will be called
|
|
the first time and when Nagios shuts down with Embedded Perl (ePN). In
|
|
particular, do not use BEGIN blocks to initialize variables.</P
|
|
></LI
|
|
><LI
|
|
><P
|
|
>To use utils.pm, you need to provide a full path to the
|
|
module in order for it to work with ePN.</P
|
|
><P
|
|
CLASS="LITERALLAYOUT"
|
|
> e.g.<br>
|
|
use lib "/usr/local/nagios/libexec";<br>
|
|
use utils qw(...);<br>
|
|
</P
|
|
></LI
|
|
><LI
|
|
><P
|
|
>Perl scripts should be called with "-w"</P
|
|
></LI
|
|
><LI
|
|
><P
|
|
>All Perl plugins must compile cleanly under "use strict" - i.e. at
|
|
least explicitly package names as in "$main::x" or predeclare every
|
|
variable. </P
|
|
><P
|
|
>Explicitly initialize each varialable in use. Otherwise with
|
|
caching enabled, the plugin will not be recompilied each time, and
|
|
therefore Perl will not reinitialize all the variables. All old
|
|
variable values will still be in effect.</P
|
|
></LI
|
|
><LI
|
|
><P
|
|
>Do not use < DATA > (these simply do not compile under ePN).</P
|
|
></LI
|
|
><LI
|
|
><P
|
|
>Do not use named subroutines</P
|
|
></LI
|
|
><LI
|
|
><P
|
|
>If writing to a file (perhaps recording
|
|
performance data) explicitly close close it. The plugin never
|
|
calls <I
|
|
CLASS="EMPHASIS"
|
|
>exit</I
|
|
>; that is caught by
|
|
p1.pl, so output streams are never closed.</P
|
|
></LI
|
|
><LI
|
|
><P
|
|
>As in <A
|
|
HREF="#RUNTIME"
|
|
>the section called <I
|
|
>Runtime Timeouts</I
|
|
></A
|
|
> all plugins need
|
|
to monitor their runtime, specially if they are using network
|
|
resources. Use of the <I
|
|
CLASS="EMPHASIS"
|
|
>alarm</I
|
|
> is recommended.
|
|
Plugins may import a default time out ($TIMEOUT) from utils.pm.
|
|
</P
|
|
></LI
|
|
><LI
|
|
><P
|
|
>Perl plugins should import %ERRORS from utils.pm
|
|
and then "exit $ERRORS{'OK'}" rather than "exit 0"
|
|
</P
|
|
></LI
|
|
></OL
|
|
></DIV
|
|
><DIV
|
|
CLASS="SECTION"
|
|
><HR><H1
|
|
CLASS="SECTION"
|
|
><A
|
|
NAME="RUNTIME"
|
|
>Runtime Timeouts</A
|
|
></H1
|
|
><P
|
|
>Plugins have a very limited runtime - typically 10 sec.
|
|
As a result, it is very important for plugins to maintain internal
|
|
code to exit if runtime exceeds a threshold. </P
|
|
><P
|
|
>All plugins should timeout gracefully, not just networking
|
|
plugins. For instance, df may lock if you have automounted
|
|
drives and your network fails - but on first glance, who'd think
|
|
df could lock up like that. Plus, it should just be more error
|
|
resistant to be able to time out rather than consume
|
|
resources.</P
|
|
><DIV
|
|
CLASS="SECTION"
|
|
><HR><H2
|
|
CLASS="SECTION"
|
|
><A
|
|
NAME="AEN165"
|
|
>Use DEFAULT_SOCKET_TIMEOUT</A
|
|
></H2
|
|
><P
|
|
>All network plugins should use DEFAULT_SOCKET_TIMEOUT to timeout</P
|
|
></DIV
|
|
><DIV
|
|
CLASS="SECTION"
|
|
><HR><H2
|
|
CLASS="SECTION"
|
|
><A
|
|
NAME="AEN168"
|
|
>Add alarms to network plugins</A
|
|
></H2
|
|
><P
|
|
>If you write a plugin which communicates with another
|
|
networked host, you should make sure to set an alarm() in your
|
|
code that prevents the plugin from hanging due to abnormal
|
|
socket closures, etc. Nagios takes steps to protect itself
|
|
against unruly plugins that timeout, but any plugins you create
|
|
should be well behaved on their own.</P
|
|
></DIV
|
|
></DIV
|
|
><DIV
|
|
CLASS="SECTION"
|
|
><HR><H1
|
|
CLASS="SECTION"
|
|
><A
|
|
NAME="PLUGOPTIONS"
|
|
>Plugin Options</A
|
|
></H1
|
|
><P
|
|
>A well written plugin should have --help as a way to get
|
|
verbose help. Code and output should try to respect the 80x25 size of a
|
|
crt (remember when fixing stuff in the server room!)</P
|
|
><DIV
|
|
CLASS="SECTION"
|
|
><HR><H2
|
|
CLASS="SECTION"
|
|
><A
|
|
NAME="AEN174"
|
|
>Option Processing</A
|
|
></H2
|
|
><P
|
|
>For plugins written in C, we recommend the C standard
|
|
getopt library for short options. If using getopt_long, check to
|
|
be sure that HAVE_GETOPT_H is defined (configure checks this and
|
|
sets the #define in common/config.h).</P
|
|
><P
|
|
>For plugins written in Perl, we recommend Getopt::Long module.</P
|
|
><P
|
|
>Positional arguments are strongly discouraged.</P
|
|
><P
|
|
>There are a few reserved options that should not be used
|
|
for other purposes:</P
|
|
><P
|
|
CLASS="LITERALLAYOUT"
|
|
> -V version (--version)<br>
|
|
-h help (--help)<br>
|
|
-t timeout (--timeout)<br>
|
|
-w warning threshold (--warning)<br>
|
|
-c critical threshold (--critical)<br>
|
|
-H hostname (--hostname)<br>
|
|
</P
|
|
><P
|
|
>In addition to the reserved options above, some other standard options are:</P
|
|
><P
|
|
CLASS="LITERALLAYOUT"
|
|
> -C SNMP community (--community)<br>
|
|
-a authentication password (--authentication)<br>
|
|
-l login name (--logname)<br>
|
|
-p port or password (--port or --passwd/--password)monitors operational<br>
|
|
-u url or username (--url or --username)<br>
|
|
</P
|
|
><P
|
|
>Look at check_pgsql and check_procs to see how I currently
|
|
think this can work. Standard options are:</P
|
|
><P
|
|
>The option -V or --version should be present in all
|
|
plugins. For C plugins it should result in a call to print_revision, a
|
|
function in utils.c which takes two character arguments, the
|
|
command name and the plugin revision.</P
|
|
><P
|
|
>The -? option, or any other unparsable set of options,
|
|
should print out a short usage statement. Character width should
|
|
be 80 and less and no more that 23 lines should be printed (it
|
|
should display cleanly on a dumb terminal in a server
|
|
room).</P
|
|
><P
|
|
>The option -h or --help should be present in all plugins.
|
|
In C plugins, it should result in a call to print_help (or
|
|
equivalent). The function print_help should call print_revision,
|
|
then print_usage, then should provide detailed
|
|
help. Help text should fit on an 80-character width display, but
|
|
may run as many lines as needed.</P
|
|
></DIV
|
|
><DIV
|
|
CLASS="SECTION"
|
|
><HR><H2
|
|
CLASS="SECTION"
|
|
><A
|
|
NAME="AEN187"
|
|
>Plugins with more than one type of threshold, or with
|
|
threshold ranges</A
|
|
></H2
|
|
><P
|
|
>Old style was to do things like -ct for critical time and
|
|
-cv for critical value. That goes out the window with POSIX
|
|
getopt. The allowable alternatves are:</P
|
|
><P
|
|
></P
|
|
><OL
|
|
TYPE="1"
|
|
><LI
|
|
><P
|
|
>long options like -critical-time (or -ct and -cv, I
|
|
suppose).</P
|
|
></LI
|
|
><LI
|
|
><P
|
|
>repeated options like `check_load -w 10 -w 6 -w 4 -c
|
|
16 -c 10 -c 10`</P
|
|
></LI
|
|
><LI
|
|
><P
|
|
>for brevity, the above can be expressed as `check_load
|
|
-w 10,6,4 -c 16,10,10`</P
|
|
></LI
|
|
><LI
|
|
><P
|
|
>ranges are expressed with colons as in `check_procs -C
|
|
httpd -w 1:20 -c 1:30` which will warn above 20 instances,
|
|
and critical at 0 and above 30</P
|
|
></LI
|
|
><LI
|
|
><P
|
|
>lists are expressed with commas, so Jacob's check_nmap
|
|
uses constructs like '-p 1000,1010,1050:1060,2000'</P
|
|
></LI
|
|
><LI
|
|
><P
|
|
>If possible when writing lists, use tokens to make the
|
|
list easy to remember and non-order dependent - so
|
|
check_disk uses '-c 10000,10%' so that it is clear which is
|
|
the precentage and which is the KB values (note that due to
|
|
my own lack of foresight, that used to be '-c 10000:10%' but
|
|
such constructs should all be changed for consistency,
|
|
though providing reverse compatibility is fairly
|
|
easy).</P
|
|
></LI
|
|
></OL
|
|
><P
|
|
>As always, comments are welcome - making this consistent
|
|
without a host of long options was quite a hassle, and I would
|
|
suspect that there are flaws in this strategy. Perhaps clear
|
|
long-options is the most important of the above choices, but not
|
|
all POSIX systems have C libraries for long options, so the
|
|
short forms must exist as well.</P
|
|
></DIV
|
|
></DIV
|
|
><DIV
|
|
CLASS="SECTION"
|
|
><HR><H1
|
|
CLASS="SECTION"
|
|
><A
|
|
NAME="SUBMITTINGCHANGES"
|
|
>New submissions and patches</A
|
|
></H1
|
|
><P
|
|
>If you would like other to use your plugins and have it included in
|
|
the standard distribution, please include patches for the relavant
|
|
configuration files, in particular "configure.in" Otherwise submitted
|
|
plugins will be included in the contrib directory.</P
|
|
><P
|
|
>Plugins in the contrib directory are going to be migrated to the
|
|
standard plugins/plugin-scripts directory as time permits and per user
|
|
requests</P
|
|
><P
|
|
>Patches should be submitted via the SourceForge and be announced to
|
|
the mailing list.</P
|
|
><P
|
|
>For new plugins, provide a diff to add to the EXTRAS list (configure.in)
|
|
unless you are fairly sure that the plugin will work for all platforms with
|
|
no non-standard software added.</P
|
|
><P
|
|
>If possible please submit a test harness. Documentation on sample
|
|
tests coming soon.</P
|
|
></DIV
|
|
></DIV
|
|
></DIV
|
|
></BODY
|
|
></HTML
|
|
> |