[dns-operations] about .in NS

[Steven Carr]

On 1 June 2017 at 02:39, Peng Yonghua <pyh at vodafonemail.de> wrote:
> Hello,
>
> I was confused about DNS authority for .in domain.
>
> $ dig in ns +short|sort
> a.root-servers.net.
> b.root-servers.net.
> c.root-servers.net.
> d.root-servers.net.
> e.root-servers.net.
> f.root-servers.net.
> g.root-servers.net.
> h.root-servers.net.
> i.root-servers.net.
> j.root-servers.net.
> k.root-servers.net.
> l.root-servers.net.
> m.root-servers.net.
>
> it shows .in is auth-resolved by root-servers.
>
> but when I run this:
>
> $ dig rediff.in +trace
>
> ; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.62.rc1.el6_9.2 <<>> rediff.in +trace
> ;; global options: +cmd
> .                       141101  IN      NS      d.root-servers.net.
> .                       141101  IN      NS      l.root-servers.net.
> .                       141101  IN      NS      m.root-servers.net.
> .                       141101  IN      NS      b.root-servers.net.
> .                       141101  IN      NS      g.root-servers.net.
> .                       141101  IN      NS      k.root-servers.net.
> .                       141101  IN      NS      c.root-servers.net.
> .                       141101  IN      NS      e.root-servers.net.
> .                       141101  IN      NS      f.root-servers.net.
> .                       141101  IN      NS      a.root-servers.net.
> .                       141101  IN      NS      j.root-servers.net.
> .                       141101  IN      NS      h.root-servers.net.
> .                       141101  IN      NS      i.root-servers.net.
> ;; Received 508 bytes from 180.76.76.76#53(180.76.76.76) in 14 ms
>
> in.                     172800  IN      NS      a0.in.afilias-nst.info.
> in.                     172800  IN      NS      a1.in.afilias-nst.in.
> in.                     172800  IN      NS      a2.in.afilias-nst.info.
> in.                     172800  IN      NS      b0.in.afilias-nst.org.
> in.                     172800  IN      NS      b1.in.afilias-nst.in.
> in.                     172800  IN      NS      b2.in.afilias-nst.org.
> in.                     172800  IN      NS      c0.in.afilias-nst.info.
> ;; Received 506 bytes from 192.203.230.10#53(192.203.230.10) in 264 ms
>
> rediff.in.              86400   IN      NS      ns.rediffmailpro.com.
> rediff.in.              86400   IN      NS      ns2.rediffmailpro.com.
> ;; Received 79 bytes from 199.249.125.1#53(199.249.125.1) in 272 ms
>
> rediff.in.              21600   IN      A       202.137.236.33
> ;; Received 43 bytes from 119.252.159.175#53(119.252.159.175) in 300 ms
>
>
> It shows .in has been resolving by afilias-nst's name servers.
> Can you help explain? thanks.

You need to FQDN "in" to "in."

If you remove the +short from your command you'll see that dig has
looked up the INternet class NS records for root.

sjcarr at verne:~ $ dig in. ns +short|sort
a0.in.afilias-nst.info.
a1.in.afilias-nst.in.
a2.in.afilias-nst.info.
b0.in.afilias-nst.org.
b1.in.afilias-nst.in.
b2.in.afilias-nst.org.
c0.in.afilias-nst.info.