Introducing 'tdns': the Teachable Authoritative DNS Server bert hubert — 20 Apr 2018


A warm welcome to DNS


2. basic


The concept of a DNS name is non-trivial and frequently misunderstood.

日本なら、JP TLD下のゾーン木を図にしてみるのがよいだろう。

3. www.ietf.org AAAA RR はどこに


'www.ietf.org' can be defined in four different places.

It could be in the 'root' zone itself, fully written out:

www.ietf.org    IN      AAAA    3600    2400:cb00:2048:1::6814:55

Or it could be in the org zone, where it might look like this:

$origin ORG
www.ietf        IN      AAAA    3600    2400:cb00:2048:1::6814:55

Or, (as is actually the case), this name could live in the 'ietf.org' zone:

$origin ietf.org
www     IN      AAAA    3600    2400:cb00:2048:1::6814:55

And finally, it is even possible that there is a zone called 'www.ietf.org',
where the record lives like this:

$origin www.ietf.org
@       IN      AAAA    3600    2400:cb00:2048:1::6814:55

4. 権威サーバーの動作

あるいはzone cutsについて。

When an authoritative server receives a query for 'www.ietf.org', it consults which zones it knows about and answers from the most specific zone it has available.


5. zone


Moin2Qmail: DNS/tdns (last edited 2020-08-18 02:04:50 by ToshinoriMaeno)