実家のデフォルトのDNSサーバだとお返事が変化するな…
$ dig +noall +answer @143.90.130.39 mastodon-japan.net
mastodon-japan.net. 60 IN A 27.133.133.36
$ dig +noall +answer @143.90.130.39 mastodon-japan.net
$ dig +noall +answer @143.90.130.39 mastodon-japan.net
$ dig +noall +answer @143.90.130.39 mastodon-japan.net
mastodon-japan.net. 42 IN A 27.133.133.36
$ dig +noall +answer @143.90.130.39 files.mastodon-japan.net
$ dig +noall +answer @143.90.130.39 files.mastodon-japan.net
files.mastodon-japan.net. 300 IN A 172.67.186.6
files.mastodon-japan.net. 300 IN A 104.21.0.137
$ dig +noall +answer @143.90.130.39 files.mastodon-japan.net
$ dig +noall +answer @143.90.130.39 files.mastodon-japan.net
$ dig +noall +answer @143.90.130.39 files.mastodon-japan.net
$ dig +noall +answer @143.90.130.39 files.mastodon-japan.net
files.mastodon-japan.net. 300 IN A 104.21.0.137
files.mastodon-japan.net. 300 IN A 172.67.186.6
NSも見えるときと見えないときとある…
$ dig +noall +answer @143.90.130.39 NS mastodon-japan.net
$ dig +noall +answer @143.90.130.39 NS mastodon-japan.net
$ dig +noall +answer @143.90.130.39 NS mastodon-japan.net
mastodon-japan.net. 86400 IN NS fay.ns.cloudflare.com.
mastodon-japan.net. 86400 IN NS buck.ns.cloudflare.com.
$ dig +noall +answer @143.90.130.39 NS mastodon-japan.net
$ dig +noall +answer @143.90.130.39 NS mastodon-japan.net
mastodon-japan.net. 86400 IN NS fay.ns.cloudflare.com.
mastodon-japan.net. 86400 IN NS buck.ns.cloudflare.com.
$ dig +noall +answer @143.90.130.39 NS mastodon-japan.net
$ dig +noall +answer @143.90.130.39 NS mastodon-japan.net
mastodon-japan.net. 86400 IN NS fay.ns.cloudflare.com.
mastodon-japan.net. 86400 IN NS buck.ns.cloudflare.com.
$ dig +noall +answer @143.90.130.39 NS mastodon-japan.net
$ dig +noall +answer @143.90.130.39 NS mastodon-japan.net
@8.8.8.8だと一貫して返事をもらえる(順番が変わることはある)