Agent monitoring behavior / Packet loss calculation

[salamonkey]

Some questions upfront:

- How does Domotz exactly measure and calculate packet loss?

- Is there a way to access the logs that Domotz is creating see the ‘source data’ for the report and compare?

- In the Domotz report - what do gray areas with no data mean? (see attached picture)?

- How does Domotz differentiate between 'Down' (red areas) and whatever the gray area is?

 

Background / setup:

- Domotz agent is installed on a Synology unit which is connected via a cable to the main switch (Unifi UDM Pro).

- One (and only one) of about 30 devices (total on the network) is consistently showing some amount of packet loss in the Domotz monitor. A fairly consistent 6.67% (with some 0% in between) but also some peaks around 80% and 86.6%. 

- The Device is an app server - connected directly via a cable to the switch. I have replaced the cable and moved to another port on the switch, just to rule out those as a possible source of error - with no difference in what Domotz shows. 

 

The issue:

- The Device is causing some issues on the application end, and the app provider is pointing to possible network issues, so I need to get to the bottom of this.

- Next to Domotz, I have started ping sessions from two other devices on the network to run for up to 2 hours. One of the devices is another application server, and the other device is the Synology unit itself - ping session from an OS level (via SSH login). 

- While the Domotz agent shows the packet loss as described above (unchanged during the other ping sessions), the other ping sessions do not show any issues, lost packets, or otherwise. Or if so, less than 1%. Attached the 1D report.

 

Also, the 6.67% increments in Domotz point to some sample set of 15 (which would correspond 15%), but I am not sure how this comes together. I’d be grateful to understand that.

Happy for any pointer that may be helpful in understanding whether there is some network issue or not. And last but not least, to get a better insight into the workings of Domotz.