Disk data displayed by AppDynamics is not the same as the data on the server

[shandi.pusghiyanto]

Dear All,

I have a problem. I'm wondering if anyone has experienced an issue where the disk data displayed by appdynamics is not the same as the data on the server. The data on appdynamics displays disk usage at OPT by 53%, while on the server by 56% there is a difference of 3%, as attached.

please advice.

Shandi Aji p

  

[shandi.pusghiyanto]

Hi all,

Can anybody help me with this problem?

thanks

[Valerie.Li]

Hi Shandi, 

The current AppD server agent does not use df command to gather disk metrics hence the discrepancy. 

[Selvaganesh.Elavarasan]

Hello Valerie,

I found the below link which was suggested by AppD to overide the default AppD disk space calculation with df calculation:

Linux includes a mechanism for reserving some disk space to ensure that the system remains functioning even if non-privileged users consume all other disk space. By default, these metrics do not include this reserved space. The total disk space reported by the agent might differ from the total disk space reported by the Linux df command or other sources.
To override this default, and to ensure that these metrics include this reserved space, run the agent with the following command-line argument:
      -Dappdynamics.machine.agent.extensions.calcVolumeFreeAndUsedWithDfCommand=true
This feature is supported for Linux versions of the Machine Agent only.

https://docs.appdynamics.com/display/PRO45/Hardware+Resources+Metrics#HardwareResourcesMetrics-confi...

[Selvaganesh.Elavarasan]

Hello Shandi,

Please go through the below link to change the default behaviour:

Linux includes a mechanism for reserving some disk space to ensure that the system remains functioning even if non-privileged users consume all other disk space. By default, these metrics do not include this reserved space. The total disk space reported by the agent might differ from the total disk space reported by the Linux df command or other sources.
To override this default, and to ensure that these metrics include this reserved space, run the agent with the following command-line argument:
      -Dappdynamics.machine.agent.extensions.calcVolumeFreeAndUsedWithDfCommand=true
This feature is supported for Linux versions of the Machine Agent only.

https://docs.appdynamics.com/display/PRO45/Hardware+Resources+Metrics#HardwareResourcesMetrics-confi...