Additionally: Even if I use Passepartout as VPN client and manually overwrite the DNS server, the iPhone does not use my local DNS server.
Although I’m pretty cautious with such assumptions, since I wouldn’t assume I’d be the first to notice something like that, it looks to me like iOS 14 has a problem getting local DNS servers to default.
iPad OS on the other hand does not, which also seems strange.
Anyway, I’m at a dead end
Hi
Maybe just to answer a few questions:
I do have OpenVPN & IPsec RoadWarrior VPNs to home. I do NOT use these to surf the Internet when I’m out of the house, but on my Macbook the PI-Hole is respected…
I NEVER surf with my iPhone, I only access mail, weather and maybe news and the railway timetable, most of these are with Apps (except for news). I do not like using a small screen…
I maybe use to test if a site is available (Firewall tests, for example!), but not really surfing.
These are settings which must be set (at least for me!)…
IOS now features a “fake” MAC Address to thwart off trackers! That’s not bad, but is not WLan dependent, it’s globally set. 
Now, I’d like my device to use the allocated DNS when at home, nothing else!
I have home control, which needs to know if I’m at home or not!
So I have to globally deactivate this - at least until Apple provides a per WLan AP setting for this.
The second one is to show that my PI-Hole is respected at home - i’ve never tested it from outside, indeed, I’ve never installed a VPN on my phone, I use it really exclusively to phone, SMS and read mail - I almost NEVER write a response on my iPhone…
This shows that my PI-Hole is used, at least when I’m at home!
My 2 cents
Andy
Hi Andy, inside my LAN works Pihole as local DNS-Sever properly. OpenVPN I tested only with the 4G-connection.
But I have traditionally disabled the private Wi-Fi address as well, for the same reason as you.
Sincerely, MArko
Hi Marko
Both Roadwarrior VPNs (OpenVPN & IPsec) work correctly, but as said, I’ve never used VPN on my iPhone…
But on my Mac, they work also using the personal Hotspot in my iPhone…
Best regards from very sunny and very cold Bodensee!
Andy
perhaps you can try it for me? 
I can test it with my old iPhone next week…
Will report.
Random question, is it possible to virtualize the Mac OS and IPhone OS in Proxmox for testing?
Hi Royce
Ever heard of a Hackintosh?
Did a triple boot on the 2010 “Netbooks” with MacOS, Linux and Windows, the second one with Mac, Linux and OpenBSD…
You can install Proxmox directly on say a newer Mac Mini, these are quite powerful little (expensive) bstards. Then it would be legal to install and run MacOS virtualized…
If you then - eg due to HA move it to other hardware - sht happens… But it’ll still keep on running. I think the Proxmox needs at least a Haswell CPU (Old anyways…)
My 2 cents
Andy
iPhone emulation is AFAIK only available in Apple’s IDE (xCode, for free!). It’s quite powerful, but you need a Mac… (Or Hackintosh…)
1 Like
I found the solution.
iPhones uses IPv4 and IPv6 simultaneous. Since Road Warrior only provides IPv4 information to the iPhone within a LAN, the IPv4 DNS server/gateway are used.
Outside it uses the IPv6-Servers.
I override this behavior by using the app Passepartout and deactivated IPv6 Gateway. It is not enough to configure only the DNS server manually.
The same configured in Viscosity on my MacBook:
Now it works.
1 Like
I actually deactivate IPv6 in a NethServer environment, be it for Win, Mac or Linux and Tablets / Smartphones.
IPv6 is also deactivated on my OPNsense for that reason…
This is not a statement for delaying IPv6 on NethServer! 
It must come with NS8…
My 2 cents
Andy
1 Like
I don’t know of any way to generally disable IPv6 on iOS.
You can’t! What you did was the right way!
(It’s only an issue in a NS environment, no issues with the rest of the Internet!)
1 Like