DNS/返答/NXDOMAIN/返答例について、ここに記述してください。
1. ns.qmail.jp
tinydns(djbdns)の動作
$ dnsq a ns.qmail.jp a.ns.qmail.jp 1 ns.qmail.jp: 80 bytes, 1+0+1+0 records, response, authoritative, nxdomain query: 1 ns.qmail.jp authority: qmail.jp 2560 SOA a.ns.qmail.jp hostmaster.m.qmail.jp 1507365818 16384 2048 1048576 2560
2. elb.amazonaws.com
noerrorがよいと思うのだが、nxdomainも返ってくる。
$ dnsq a elb.amazonaws.com a.gtld-servers.net 1 elb.amazonaws.com: 167 bytes, 1+0+4+4 records, response, noerror query: 1 elb.amazonaws.com authority: amazonaws.com 172800 NS u1.amazonaws.com authority: amazonaws.com 172800 NS u2.amazonaws.com authority: amazonaws.com 172800 NS r1.amazonaws.com authority: amazonaws.com 172800 NS r2.amazonaws.com additional: u1.amazonaws.com 172800 A 156.154.64.10 additional: u2.amazonaws.com 172800 A 156.154.65.10 additional: r1.amazonaws.com 172800 A 205.251.192.27 additional: r2.amazonaws.com 172800 A 205.251.195.199
$ dnsq a elb.amazonaws.com u1.amazonaws.com 1 elb.amazonaws.com: 107 bytes, 1+0+1+0 records, response, authoritative, noerror query: 1 elb.amazonaws.com authority: amazonaws.com 3593 SOA pdns1.ultradns.net hostmaster.amazon.com 2014061439 180 60 2592000 3593
$ dnsq a elb.amazonaws.com r1.amazonaws.com 1 elb.amazonaws.com: 109 bytes, 1+0+1+0 records, response, authoritative, nxdomain query: 1 elb.amazonaws.com authority: amazonaws.com 3593 SOA dns-external-master.amazon.com hostmaster.amazon.com 2012708585 180 60 2592000 3593
hidden primaryがありそう。
3. akamai
watchA/www.ana.co.jp.edgekey.net に現れる jp.edgekey.net など
-- ToshinoriMaeno 2017-10-08 01:55:11