I have a pi-hole and pivpn running on raspberry pi 3 in a remote location - my parents home. I've had this working very well in the past until I updated pi-hole. The VPN part works very well. It blocks ads as expected. The local blocking is not as successful now for some reason.
I have Teamviewer access to a desktop computer running Win7 which I use as a test machine. When I use it to test if pi-hole is working, the pi-hole admin page does not appear to update the quantity of DNS Queries Blocked Today. I use fark.com as my test page as I know it contains ads that pi-hole blocks. The ads on fark.com are not blocked locally, but they are via vpn.
My home network is similar in setup with pi-hole and pivpn and both local and vpn queries return an increase in DNS queries blocked without any issues.
I've reviewed other topics that explain how to install pi-hole and pivpn and followed many instructions, yet my pi-hole is still not working as desired. I'm usually pretty good at figuring this out, but I cannot get this one figured out.
I'd be happy to post whatever info is required from my setup to get this sorted out.
The query log for my parent's network do show some DNS entries blocked, but yet I know more should be present. I'm not entirely sure how to troubleshoot this and I have uninstalled pi-hole and re-installed to try to fix. So far, I'm unsuccessful.
The internet modem setting for DNS is set to 192.168.1.250 which is the IP address of the raspberry pi. My pi hole is using my the ISP's DNS servers 75.153.176.1 and 75.153.171.114.
The ISP is also a IPTV provider and the set top boxes seem to get cranky and not work when I use other DNS servers like Google. I recently changed from the Google DNS servers because of this. My folks got tired of turning on TV and having it not work and then calling me to fix it by returning the modem DNS settings to default and then power cycling everything.
Once IPTV boxes were working again, I would change the modem's DNS servers to the raspberry pi 192.168.1.250 and everything would be good again for about a month.
If we have several choices of DNS server's in the pi hole setup, I don't understand how the ISP's servers would cause this behaviour. But, I do not know much about DNS.
If it helps, the raspberry pi itself does block ads. localhost shows up in the query log and blocks ads as expected. The Win7 client I use for testing does show DNS queries in the pi hole admin console but they all seem to show as "OK (forwarded)"
Does your network have an IPv6 internet connection? http://ipv6-test.com/
If not, then are those green queries IPv6 queries? If so, it doesn't really matter what they resolve to, since your device can't reach the internet via IPv6. If the queries are IPv4 though, then that doesn't make sense (dnsmasq answers localhost correctly, but other devices incorrectly?).
Thank you for the test site. Yes, the network with issues has IPv4 and IPv6. Hmmm. I've added the IPv6 DNS servers from the ISP in the pihole admin console. Now I have DNS 1 75.153.176.1, DNS 2 75.153.171.114, DNS 3 2001:568:ff09:10a::55 , and DNS 4 2001:568:ff09:10a::114. Same issue. Still not blocking.
update
Overnight the issue has resolved itself. Ads are now blocked as expected both via VPN and locally. I guess this was caused by the Win7 machine's DNS cache? I did flush the cache with ipconfig /flushdns, clear the browser's cache and cookies, and even rebooted the machine.
Whatever, I'm happy. Thank you for your assistance
update
This afternoon the issue has returned. Local client is not blocking ads as expected after it was successfully this morning with no changes at all.
update
I decided to check the Windows IPv6 settings. Sure enough the IPv6 DNS servers were coming from the ISP's router and were the defaults from the ISP. This caused the local Win7 client to bypass the pi hole! I updated the router's default IPv6 DNS server to point to the raspberry pi IPv6 address and all issues are resolved.
