> Whatever   M&M   does   has   nothing  to  do  with  my  post  about
> "propagation".

Your  world-renowned, subject-matter-expert employer uses the term you
decry  as  the  choice of "unknowing, misleading people." If you can't
stop them from using it, you obviously can't expect less expert people
to stop using it.

> Master/slave   zone  replication,  whether  intra  or  internet,  is
> typically   accomplished   within  seconds  via  NOTIFY.  It's  very
> definitely not the multi-day "propagation delay" that non-DNS people
> seem  to  imagine  is  the  cause of their internet DNS questions or
> problems.

Your  presentation  of how "propagation" is used in common parlance is
incomplete.  It is widely used to describe replication delays for both
zone  transfers  and  cached  records.  We  hear  it  used  equally in
reference  to  A,  MX,  and NS records. You can verify this simply via
Google.

> With  TTLs  in general tending to be regrettably smaller and smaller
> (to  the  point  of being so short that some NSs ignore the record's
> TTL  field  and  add  their  own,  longer  TTL), the expiry of stale
> records  from  cache is less of a problem.

"Less  of  a  problem" as time goes by does not mean that cached stale
RRs  are  not  (a)  still  common  causes  of  confusion, and (b) what
providers explicitly refer to when they speak of propagation delays.

> Probably  the  longest TTLs are 2 days as seen in the .com and other
> TLD parent servers.

And  it's  that  2-day  period that's validly pointed out by providers
cautioning  their  customers, in addition to another 1-day or half-day
pad  for  reboots  in  many  cases,  when they speak of "propagation."
Should  there  instead  be  no warning, or maybe a fraudulent claim to
provide instantaneous global changes? Remember, not everyone gets paid
by the hour to answer people's stupid support questions.

> Expiry  of  stale  records  from  cache is unavoidable. The way "DNS
> propagation" is often used is that the changes in delegation records
> will require several days to become effective...

That's  one way. It is one of two ways. Google for a couple of minutes
and you will see the reality of the term's usage "in the wild."

There  is  no  way  that one can claim that replication delays are not
vastly  common  causes  of DNS non-problems (i.e. behavior expected by
experts--but that still causes confusion to those _not_ expecting it).
Since  they  are hands-off in nature, it can be convenient for experts
(or  those  posed  as  such)  to scapegoat replication delays to avoid
dealing  with what are real configuration issues. This does not change
the  validity  of  having  user-friendly  names for expected behavior.
Pretending that replication delays/propagation will never be "felt" by
non-DNS admins or end users is ridiculous.

--Sandy


------------------------------------
Sanford Whiteman, Chief Technologist
Broadleaf Systems, a division of
Cypress Integrated Systems, Inc.
e-mail: [EMAIL PROTECTED]

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