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SNMP vs SSH Monitors




I am wondering if there is a way to set up a CPU monitor that uses SSH for a linux Red Hat server. I was able to get other things working, but not a CPU monitor. I see SNMP CPU monitors but these fail -- maybe because I need to open firewall ports?

I guess I am not understanding the difference between the two protocols as well as I could.


cpu-load prgt snmp snmp-sensor ssh

Created on Dec 28, 2015 4:57:30 PM

1 Reply



Dear user

SSH sensors log into the device using a secure shell connection. Then the sensor transmits one or more commands and reads the output, which is then further processed by the sensor to extract the needed data.

SNMP sensors read a value directly, using the simple network management protocol. This requires an SNMP daemon running on the computer which you want to monitor.

PRTG does not come with an SSH CPU sensor, but you could use the SSH script sensor to write your own SSH CPU sensor. This command


gives you three numbers, which are CPU load averages for different time spans. The first value usually gives you the one-minute-average. A custom SSH CPU sensor could use that command, followed by other commands to cut out only the first numeric value and create a return output which conforms to the PRTG custom sensor API (which is returncode:value:message.)

The actual SSH script has to be located on the monitored machine, in the /var/prtg/scripts path.

Created on Dec 29, 2015 12:47:42 PM by  Arne Seifert [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.