North American Network Operators Group

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Re: mail does bounce (was: Customers down?)

  • From: jlewis
  • Date: Sun Jan 02 01:28:29 2000

On 1 Jan 2000, Sean Donelan wrote:

> On Sat, 01 January 2000, "Steven J. Sobol" wrote:
> > What I was referring to was a situation where the domain does exist in the
> > root nameservers but the authoritative nameservers are unavailable.
> So .COM exists in the root servers?  How do you decide to treat second
> level domains (i.e. versus third level domains
> (i.e. versus third level domains under country code
> domains.

Sendmail is smart enough to distinguish between a DNS lookup timing out
(authoratative name servers unreachable) and getting an nxdomain response
(authoratative name server says host doesn't exist).  In the first case,
the message is queued and delivery retried periodically.  In the second,
the message bounces.

 Jon Lewis *[email protected]*|  Spammers will be winnuked or 
 System Administrator        |  nestea'd...whatever it takes
 Atlantic Net                |  to get the job done.
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