https://en.wikipedia.org/wiki/MaraDNS https://en.wikipedia.org/wiki/MaraDNS https://maradns.samiam.org/ https://maradns.samiam.org/ https://github.com/samboy/

https://en.wikipedia.org/wiki/MaraDNS https://en.wikipedia.org/wiki/MaraDNS https://maradns.samiam.org/ https://maradns.samiam.org/ https://github.com/samboy/MaraDNS https://github.com/samboy/MaraDNS for really being lean&mean enough to run it effortlessly on something like (even older) Raspberry Pis or similar SBCs, or routers running things like OpenWRT/DDWrt or similar. While it has no GUI, it can do everything you asked for. F.E. snapshotting its data to file, either via its internal scripting language (Lua), or cron jobs. To be further improved by using some upstream https://en.wikipedia.org/wiki/Alternative_DNS_root https://en.wikipedia.org/wiki/Alternative_DNS_root which doesn't do the shit you fear in the first place, thereby maybe widening the timeframe before SHTF is hitting you. Or at least something from here https://en.wikipedia.org/wiki/Public_recursive_name_server https://en.wikipedia.org/wiki/Public_recursive_name_server I'd recommend Mullvad, using it ATM because it's working excellently for me, without adding any noticable latency. But that may vary with your location. Please note: Can be used without its VPN service https://mullvad.net/en/help/dns-over-https-and-dns-over-tls https://mullvad.net/en/help/dns-over-https-and-dns-over-tls You can use the ad/game/porn-blocking in various levels or steps, or not at all. I think it's nice to have as a first layer of defense for gadgets where it's impractical to install adblocking on device. HTH