False Negatives

[David Johnson]

I figured out my problem. As usual, user error.  Which explains why the service check command failed, and the host check command succeeded when they were the same thing.  I had the NRPE checks pointing to the wrong NRPE server for the service checks.  Actually, it's surprising that the other 30 worked.   All is good. My bad.


-----Original Message-----
From: nagios-users-admin at lists.sourceforge.net
[mailto:nagios-users-admin at lists.sourceforge.net]On Behalf Of Marc
Powell
Sent: Thursday, August 11, 2005 10:52 AM
To: nagios-users at lists.sourceforge.net
Subject: RE: [Nagios-users] False Negatives




> -----Original Message-----
> From: nagios-users-admin at lists.sourceforge.net [mailto:nagios-users-
> admin at lists.sourceforge.net] On Behalf Of David Johnson
> Sent: Thursday, August 11, 2005 10:37 AM
> To: Hosey, Chester; nagios-users at lists.sourceforge.net
> Subject: RE: [Nagios-users] False Negatives
> 
> The manual running of the plugins succeeds every time.  The nagios
running
> fails every time.  I must say that I get two different failures.
> 
> 1. One falsely failing server returns: "Server answer:"

Looking at the src for check_ssh (which I assume you are using), it
makes a connection on the specified port and looks for "SSH" as the
first 3 characters in the first line of output. If it doesn't find it
then it prints "Server answer:" then the text that it did see. In your
case it looks like it's either getting a blank line or nothing at all.
I'd try that test manually using telnet several times in a row just to
make sure that you're seeing the expected output. Perhaps also turn up
logging for your sshd. Maybe there's some indication of the problem
there.

> 2. The other falsely failing server returns a CHECK_NRPE timeout of 10
> seconds (which is odd because I set the timeout to 30 and did a hard
> restart).

There are two places where the timeout could be coming from. Each plugin
may have their own timeout value (usually -t) and nagios has a master
timeout value in nagios.cfg (service_check_timeout). The master timeout
will always override the plugin timeout value if it's shorter (since
nagios has no idea what the plugin timeout might be). If -t=45 for a
plugin but service_check_timeout is 10 then you'll still only get 10
seconds.

--
Marc


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-------------------------------------------------------
SF.Net email is Sponsored by the Better Software Conference & EXPO
September 19-22, 2005 * San Francisco, CA * Development Lifecycle Practices
Agile & Plan-Driven Development * Managing Projects & Teams * Testing & QA
Security * Process Improvement & Measurement * http://www.sqe.com/bsce5sf
_______________________________________________
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https://lists.sourceforge.net/lists/listinfo/nagios-users
::: Please include Nagios version, plugin version (-v) and OS when reporting any issue. 
::: Messages without supporting info will risk being sent to /dev/null