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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">As far as passive checks, just use your script as an eventhandler. As for dynamically adding, I wish too
</span><span style="font-size:11.0pt;font-family:Wingdings;color:#1F497D">J</span><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"> My restart times are now like 15-20 minutes whenever I make a config change or update hosts.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Dan<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> Felipe Cecagno [mailto:fcecagno@gmail.com]
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<b>Sent:</b> Thursday, February 09, 2012 7:32 PM<br>
<b>To:</b> nagios-users@lists.sourceforge.net<br>
<b>Subject:</b> [Nagios-users] Dynamically add/remove hosts on Nagios<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Hi everybody,<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">This is the first time I'm posting on this mailing list, so I'm sorry if my question was already discussed here - I tried to find information about it on the mailing list and also on Nagios documentation + googling, but couldn't find it.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Well, I'm setting up Nagios to monitor a group of servers in a cloud environment. I decided to use passive checks, so I will have one Nagios central monitor and all servers push statistics to Nagios using NSCA. Everything is OK so far.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">The problem is that I want to add and remove instances dynamically, I don't want to manually modify hosts.cfg on the central each time I change my infrastructure. So my idea was that when a new instance gets up, it will send to Nagios something
like (always using NSCA):<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">"localhost Server UP 0 <new instance IP>"<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Nagios I would create a new service on localhost to handle this passive check.<o:p></o:p></p>
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<p class="MsoNormal">I've created a Python script (that uses pynag) to modify the hosts.cfg file in order to add and remove host definitions. When Nagios receives this passive check, I would call the script to modify the hosts definition files, and a cron job
would execute every minute to look for modifications on hosts.cfg and make Nagios reload the definition files.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">My doubts are:<o:p></o:p></p>
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<p class="MsoNormal">- is there a smarter way to do that (dynamically add and remove hosts from Nagios)?<o:p></o:p></p>
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<p class="MsoNormal">- since my "Server UP" service uses passive checks only, how do I make Nagios call my script to modify hosts.cfg every time it receives the passive check?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Any thoughts/suggestions would be appreciated. :)<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Thank you in advance,<o:p></o:p></p>
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<p class="MsoNormal">Best regards,<br clear="all">
<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">--<o:p></o:p></p>
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<p class="MsoNormal"> Felipe Cecagno<o:p></o:p></p>
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<p class="MsoNormal"> Mconf Development Team<o:p></o:p></p>
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<p class="MsoNormal"> <a href="https://mconf.org/" target="_blank">https://mconf.org</a><o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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