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I'm trying to monitoring switch with Nagios. I had made everything like in this tutorial, but I'm getting Status Information in Nagios browser window like this:

(Return code of 127 is out of bounds - plugin may be missing) 

So I had checked the google and found that I need to install check_snmp plugin. So how can I do it?

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migrated from Dec 22 '10 at 3:15

This question came from our site for professional and enthusiast programmers.

check_snmp is IIRC installed by default. check /usr/lib/nagios/plugins. Also what brand of switch are you trying to monitor? – Zypher Dec 22 '10 at 3:21

That error message is very misleading, as you will get it for a number of issues that have nothing to do with a missing plug-in. Most commonly you will receive it if Nagios cannot communicate with the target. Start by checking that the Nagios server has permission to read SNMP data from the switch.

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Thanks for useful link! I uncommented this line

# cfg_file = / usr / local / nagios / etc / objects / switch.cfg nagios.cfg

in and it worked. It was my mistake.

Also, the file check_snmp was missing from /usr/local/nagios/libexec, so I downloaded the plugin from here and installed it.

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It would be helpful if you'd provided the relevant parts of the config.

If you followed the instructions you referenced, you probably already have check_snmp built and installed (by default it's in /usr/local/nagios/libexec) however if the Makefile can't find the required libs at compile time it won't build the executable. Go have a look.

If it has been built, did you add an entry to commands.cfg for the script?

See also

If you're still stuck show us the relevant command, host and service entries from your config

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