2020-03-25 It's 2020 and github doesn't support IP version 6 2 months ago
Several of the machines here at home have IPv4 to the outside world disabled, simply to find every ancient service or program that still lives in the old world. Today I found one of those while installing dehydrated to automatically renew Let's Encrypt certificates. Indeed, github has no IPv6 support. It tries to be a modern service, but lacks an AAAA record. The solution is simple: use a webproxy to solve this. The only reason I still have a squid webproxy running is to be able to access IPv4-only http/https services from those hosts, so setting the http proxy in the global git config helped. I'm just surprised github doesn't support IPv6. Update: After some searching I found Github users have been asking about IPv6 connectivity since at least 2018 and the "solution" is that they currently don't support IPv6 and the request is on some list.