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Memory values are wrong




I'm using the SNMP Memory sensor to monitor the free memory on CentOS 7 servers. The results are totally wrong.

The command "free -h" displays this:

total used free shared buff/cache available Mem: 3.6G 1.4G 984M 36M 1.2G 1.9G Swap: 0B 0B 0B

PRTG Shows me 61% free. So the sensor might measure something wrong. What can i do to fix this?


centos memory snmp

Created on Mar 10, 2020 8:15:19 PM

1 Reply



Hi there,

Thank you for your post.

The sensor only considers real free memory as free while not taking in account cached and buffered memory.

Please check out this other Knowledge Base post for an alternative.

I hope this helps.

Kind regards,
Andreas Günther
Tech Support, Paessler AG

[email protected]

Created on Mar 11, 2020 8:48:56 AM by  Andreas Günther [Paessler Support]

Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.