I've set up pihole w/ cloudflared + pivpn on a raspberry pi 2b+
Everything seems to be working properly when connected to my internal WIFI (cable modem / router combo) on an Android client using the OpenVPN application. The client connects, and I can see activity in the vpn logs in that instance. I can't seem to connect with my Android client on cellular data or outside of my Wifi.
I've forwarded ports 1194 on my router to point to the raspberry pi internal IP (on same port), which is a reserved ip on my internal network. Externally, I'm able to ping my router's IP when forwarding port 80, either via the ip directly, or through Duck DNS which I have setup to point to my router.
Pihole is configured to listen on both tun0 or eth0, and upstream DNS is through cloudflared DNS over HTTPS, with pihole set to DNS of 127.0.0.1#5053. This was a pretty vanilla installation on Raspbian jessie following the common guides for setting up both pihole and pivpn through the 1 step install. Adblocking and pihole functionality seems to be working as intended
My questions are:
1) What configuration parameters should I be looking at to troubleshoot; and 2) I've heard ISPs with a NAT between my modem / router might interfere with this functionality; is there a way to determine if this issue is upstream of my network, or with some way I have configured the services on the raspi?
Thanks for any help / pointers.