Quoting Didier Kryn (kryn@???):

>     Any reading to recommend about recursive, authoritative or
> what else name servers ?

Not trying to be perverse, but: What would you like to know?

I'll give you two answers, where the first one is my effort to avoid
seeming to promote my own writings. Zytrax has over the years had truly
excellent online materials about DNS, and the current iteration is this
really good (gratis but not libre) online book, _DNS for Rocket
Scientists_:

http://www.zytrax.com/books/dns/

Also, over the years when I was one of the editors for _Linux Gazette_,
I wrote an intermittant series of articles on aspects of DNS for the
interested layman. All of my _Linux Gazette_ articles are collected
here, along with a picture of me gazing off myopically into the middle
distance wondering why there is a blond-reddish caterpillar on my upper
lip: http://linuxmafia.com/~rick/moen-lg.html
(The hairy caterpillar eventually pupated and flew away, i.e., I no
longer have facial hair, as the Devuan regulars who've seen me on video
chat are aware.)

I might immodestly suggest the slightly whimsical article (linked above)
' The Village of Lan: A Networking Fairy Tale' as a reasonable place to
start, as it disambiguates the several types of DNS namserver software
(recursive vs. authoritative vs. forwarder) using a quaint metaphor.
Also, an earlier article 'The Basics of DNS' (likewise linked) attempted
the same thing with less whimsy.

Last, further straining the limits of Scandinavian-American
self-deprecation, I might recommend my concise bestiary of all know DNS
software for Linux, classifying them by category:
http://linuxmafia.com/faq/Network_Other/dns-servers.html

-- 
Rick Moen                      "The correct plural forms are as follows:
rick@???            surgeons general, brothers-in-law, Spiders-Man."
McQ!  (4x80)                                              -- @FakeAPStylebook