/shrug Just curious what is happening, is this normal and expected.
Actual Behaviour:
I'm running pi-hole the latest version on my RPi. I have my own IPv6 prefix, but I've set up pi-hole to use ULA.
When I check the long-term data, I see that in the past week, the top client has been localhost (127.0.0.1), that made 75k requests. Majority of these requests are PTR IPv6 queries (ip6.arpa). To make things more puzzling, these occur at regular 30min intervals:
After spelunking in this forum, I learned that these requests are normal, as it's pihole itself checking the validity of the hostnames. However, the sheer amount of the requests is still too high for calling it normal.
Also, some posts suggest adding entries to 01-pihole.conf (I opted to add them to 02-pihole-lan.conf) like:
server=/x.y.z.c.0.d.f.ip6.arpa/fd0c:yadda::1
This should ensure that pihole will be responsible for resolving the name. However, it seems not to be working for me. I tried running dig -x <hosts_ula> @<pihole_ula>, and it returns nothing.
More precisely, they could be normal as long as they occured in bunches once every sharp hour, and only for local network addresses - those would be attributable to Pi-hole retrieving hostnames for known local network addresses.
You want to check what IP address is issuing those requests - some devices proclaim themselves to be named localhost (e.g. some Samsung Smart TVs).
You may do so by hovering your mouse over the client name in Pi-Hole's Query Log or by taking a look at the coresponding entries in /var/log/pihole.log.
looking at your screenshot this is not the case so they are not triggered by your Pi-hole itself but by a third party software on your RPi (or maybe even by the system itself)
