Hi Thomas,

Please try disabling System Information for the QNAPs, you find it in "Settings" tab of a device in section "Advanced Network Analysis". Let us know if this helps, we've also had a case where we've seen that disabling system information did not stop PRTG to run those additional SNMP queries nevertheless once a day, which triggered then those alarms on the QNAPs. We have a bug ticket open for this.

Alternatively you could disable or adjust this DDoS detection on the QNAP as described here.

Kind regards,

Erhard

Hi Erhard

I have disabled "system information" on both devices yesterday and now I have received a DoS from one QNAP

Now I will follow the steps to disable DDoS on the QNAP device

Best regards Thomas

Hello Thomas,

Yes, that's possible, it is possible that even when System Information is disabled, those queries are still being performed every now and then, we're currently looking into that.

Kind regards,

Erhard

Hello there,

I just wanted to follow up on this case. With PRTG 19.1.48.2891, the bug causing DDoS alarms on QNAP devices was fixed.

More details can be found here. Most of the changes can be found in version 19.1.48.2868 of February 2nd 2019.

Kind regards,

Erhard