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I need to check the status of power supply units Cisco 7604 using Nagios. I decided to use the plugin check_snmp:

/usr/local/libexec/nagios/check_snmp -H -o
SNMP OK - 1 | iso.


#show environment alarm threshold
environmental alarm thresholds:

power-supply 1 fan-fail: OK
  threshold #1 for power-supply 1 fan-fail:
    (sensor value != 0 ) is system minor alarm

How to set the CRITICAL for Nagios (CRITICAL=0, OK=1)?

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up vote 1 down vote accepted

You can do this easily with the negate plugin.

(It's exactly what negate is for.)

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I can not understand how to work with it: # /usr/local/libexec/nagios/check_snmp -H -o -c 1 SNMP OK - 1 | iso. and # /usr/local/libexec/nagios/negate /usr/local/libexec/nagios/check_snmp -H -o -c 1 SNMP OK - 1 | iso. – Allan Sundry Jul 19 '13 at 9:46
Read the output of "negate --help". You probably want something like "negate -s -o CRITICAL -c OK" and then your usual plugin call. – Keith Jul 19 '13 at 18:54
The problem was a missing parameter "-s". Thank you! – Allan Sundry Jul 22 '13 at 6:30

To check the power supply into the Cisco 7604 you can use the plugin

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