Nagios reporting high memory usage but server doesn't.

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mjr2015

Nagios reporting high memory usage but server doesn't.

Post by mjr2015 »

I'm monitoring my linux server by snmp and I'm receiving the following alert

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Physical memory: 89%used(28738MB/32163MB) (80%) : WARNING
however when I log into the server itself It says I am

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SERVER:~$ free -h
              total        used        free      shared  buff/cache   available
Mem:            31G         21G        3.3G        119M        6.6G        9.3G
Swap:          8.0G          0B        8.0G
any idea why it's alerting like this?
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cdienger
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Re: Nagios reporting high memory usage but server doesn't.

Post by cdienger »

Are you running the command on the XI side at the same time that the free command is being run on the monitored server? The check_snmp_storage_wizard.pl plugin pulls the OIDS holding the used and free values and divides one into the other to determine usage. Used can fluctuate and may differ from what the OID reports - try running "free -m" to get the output in megabytes reflect more of what the plugin sees.
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mjr2015

Re: Nagios reporting high memory usage but server doesn't.

Post by mjr2015 »

as close as possible:

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$free -m
 free -m
              total        used        free      shared  buff/cache   available
Mem:          32163       21953        1709         106        8500        9647
Swap:          8191           1        8190

$date
Tue 15 Jan 08:43:40 GMT 2019

from nagios:
2019-01-15 08:42:35 Physical memory: 95%used(30476MB/32163MB) (>90%) : CRITICAL
scottwilkerson
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Re: Nagios reporting high memory usage but server doesn't.

Post by scottwilkerson »

Can you post the full command that nagios is running (from the CCM) for this check?
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mjr2015

Re: Nagios reporting high memory usage but server doesn't.

Post by mjr2015 »

scottwilkerson wrote:Can you post the full command that nagios is running (from the CCM) for this check?

it's polling via SNMP

check_xi_service_snmp_linux_storage! --login=XXXX --passwd=XXXX --privpass=XXXXX --protocols=sha,aes -m Physical -w 80 -c 90 -f
scottwilkerson
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Re: Nagios reporting high memory usage but server doesn't.

Post by scottwilkerson »

Looking at your results compared to the free comman you issues it looks correct.

The SNMP check takes all Physical memory into account including that which is being used for buff/cache
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