1. dnscache
委譲のNSを返答してくる。
$ dig -t ns odns.info @127.0.0.1 ; <<>> DiG 9.18.1-1ubuntu1.2-Ubuntu <<>> -t ns odns.info @127.0.0.1 ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 1119 ;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 0 ;; QUESTION SECTION: ;odns.info. IN NS ;; ANSWER SECTION: odns.info. 3595 IN NS moin.qmail.jp. odns.info. 3595 IN NS b.ns.qmail.jp. ;; Query time: 0 msec ;; SERVER: 127.0.0.1#53(127.0.0.1) (UDP) ;; WHEN: Thu Oct 27 13:39:30 JST 2022 ;; MSG SIZE rcvd: 73