Indeed, I don't think it's possible to prevent the Velops from sending these requests, it appears to be part of how the mesh functions to detect clients across the area of coverage. Between them they send 100+ requests every 30 seconds, wiping everything off the Query Log.
That would include firmware update checks and possibly any analytics reporting, although in testing with my friend we reviewed the long-term data logs and couldn't find either. Some functionality is managed via their smartphone apps or web apps, so they may use client devices for those things and those would be covered by Pi-hole.
No I wasn't aware that was possible, but it could explain the traffic volume. What is the default TTL for Pi-hole PTR responses? Is this updated using a dnsmasq config file? The PTR requests were not blocked.
Since these are now going to the original router's DNS, and the Velops continue to function for client discovery and client features, it's not clear to me if these PTR requests are being answered by the original router, since the Velops and clients can access both subnets.
ONT --> 'wan' Original router 192.168.0/24 'lan' --> 'wan' Velop parent node 192.168.1/24 'lan' --> Clients and Velop child nodes
This is in normal mode; they also support bridge mode sitting on the original subnet, at the expense of client functions such as parental control.
Additional observations – the Velops can replace an existing router and take over PPPoE directly. In that case there would be no original router's DNS to use in the process I posted. For people in that situation I was wondering whether the same workaround could be used but simply pointing the Velops to a dummy address.
This would mean they try and fail to send their PTR requests there, and have no external DNS of their own, but at least Pi-hole is kept clear of the noise. Then again they may become very unhappy. In that case perhaps an old router can be repurposed as a second LAN DNS server, just to act as a sink for the Velops.
If someone has Velops taking over PPPoE and wants to try this it would be interesting to know how they behave. [ Edit – post by @zetafish saying that blocking PTRs made his Velops "behave badly" ]
There's a feature request for the ability to ignore domains in the Query Log. It's very popular but it's clear from the dev posts that it's not straightforward. I'm just wondering if the approach I detailed in a reply there might be one way to achieve it? Or does Pi-hole 6 have this ability?
If this was available it would allow the Velops to continue to be filtered by Pi-hole without taking over the Query Log and making it unusable for normal ad-blocking diagnostics, but I appreciate the comments in that thread re the difficulties.