[dns-operations] why 120s?

[Peter Koch]

On Wed, Aug 17, 2011 at 03:16:19PM +0800, ?????????? wrote:
> why is is deemed long enough time. Maybe it is too long or maybe too short. Bind recursor tells clients that authority is server failure before waiting for 30s without being responsed.  So it is deduced that Bind think 120 is too long. 

there's a difference between declaring failure for a specific request
with returning SERVFAIL and declaring a remote server "dead" with the consequence
of not using it for further resolution.

For the genesis of that section in RFC 2308, you may want to consult the
IETF DNSIND WG's archive ("namedroppers" mailing list back then).

-Peter