Blocky is a DNS proxy for the local network written in Go with following features:

Blocking of DNS queries with external lists (Ad-block) with whitelisting
Definition of black and white lists per client group (Kids, Smart home devices etc) -> for example: you can block some domains for you Kids and allow your network camera only domains from a whitelist

periodical reload of external black and white lists

blocking of request domain, response CNAME (deep CNAME inspection) and response IP addresses (against IP lists)

Caching of DNS answers for queries -> improves DNS resolution speed and reduces amount of external DNS queries

Custom DNS resolution for certain domain names

Serves DNS over UDP, TCP and HTTPS (DNS over HTTPS, aka DoH)

Supports UDP, TCP and TCP over TLS DNS resolvers with DNSSEC support

Supports DNS over HTTPS (DoH) resolvers
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This repository contains a blacklist.txt of XMPP domains that are used by spammers and do not react to abuse complaints. Servers are added and removed according to the following rules. The track record leading to addition or removal is documented in the respective git commit.

How to configure nginx to block certain user agents from accessing a site.