Disable Recursion problem

Disable Recursion problem

Post by Jonathan de Boyne Pollar » Wed, 04 Jun 2003 20:58:21



HM> [...] a DNS server handles a "recursive query" any way it can:
HM>     Many times from its own authoritative zones -- no recursion
HM>          involved.
HM>     Possibly from its cache -- no recursion involved.
HM>     By forwarding -- the DNS forwarder does the
HM>          recursion (maybe)
HM>     By recursing through the DNS name space -- RECURSION.

You have the wrong definition of "recursion" there.  The process of following
a chain of delegations from one set of content DNS servers to another,
starting at some root servers, is termed "resolution"; as exemplified in
section 6.3 of RFC 1034.  It is not termed "recursion".  "Recursion" is
something else.  The definition of "recursion" is quite simple:  It is the act
of a server sending back-end queries (of _whatever_ sort) to another server.
Both query resolution, where back-end queries are sent to content DNS servers,
and forwarding, where back-end queries are sent to proxy DNS servers, are
forms of recursion.

So your taxonomy should have read:

HM*> [...] a DNS server handles a "recursive query" any way it can:
HM*>     Many times from its own authoritative zones
HM*>                 -- no recursion involved.
HM*>     Possibly from its cache
HM*>                 -- no recursion involved (directly, at that time).
HM*>     By forwarding, with the forwardee doing the resolution
HM*>         -- recursion is involved.
HM*>     By performing the query resolution itself
HM*>         -- recursion is involved.

 
 
 

Disable Recursion problem

Post by William Stace » Thu, 19 Jun 2003 03:55:14


Agreed. :-)