LibreNMS & QNAP = [SNMP] DoS detected

Hi,

Issue : https://github.com/librenms/librenms/issues/5389

This Is most likely just because of the volume of snmp queries we do. If you don’t expose snmp to the outside world then disable the checks in your qnap

A similar issue has affected me since the February 17th update. All 4 of my qnaps stopped responding to snmp queries but the qnap log has no mention of DoS. If I restart the service on the qnap it works for a few minutes then stops (i’m guessing until librenms polls it). I am working with qnap to confirm on that end if it is a security measure. I have removed and re-added 2 of the qnaps from librenms and the problem has gone away for for them. Before I reset the other 2 is there any info I can get for you that will help you to address what happened to cause this?
[Edit] I have turned off the Qnap DDoS detection and it still occurs. I also noticed that it happened right after an update that changed some of the qnap polling code. Barring any feedback by the devs by tomorrow I will just delete and re-add the devices. Since it works on fresh devices I assume that it is just a glitch that has occurred because of the code change and update.

I can’t remember the exact info but do SELECT * FROM sensors WHERE device_id=X; in mysql - replace X with the device_id. Look for an OID which ends in a . (they should end up in numbers). Delete that one rogue value.

Thanks. It wasn’t one rogue one ending in “.” but 4 extra long ones. See snippet below:

All fixed now.