dns quandry

[Barry Margolin]

In article <a2q7tk$fas at pub3.rc.vix.com>, wmr <rmeisner at meridia.org> wrote:
>
>I have an issue that is affecting email that I believe may be a dns
>issue.
>When a user outside of our domain sends mail to us, my mail servers'
>log reports that the domain cannot be resolved.
>Every once in a while, my user will receive a message from this
>person/domain to my surprise.

This usually suggests inconsistent responses from the different nameservers
that the domain is delegated to.

>If I then use nslookup for that domain, for A, MX and ANY records, I
>get a response.

Did you query *all* the servers for the domain?  Did you make sure you set
the "norecurse" flag when querying them?

>Further, using nslookup on our domain, A, MX and ANY queries are
>correctly responded to.
>I can send email to this person/domain without a problem.
>Perhaps I am using the wrong tool? (nslookup)

There are some web sites that will do exhaustive tests of a domain's
servers.  Sorry, I don't have any URLs handy.

> This
>problem seems to only happen for 3 outside domains.

Why are you protecting their identity?  If you posted the domains, someone
would probably have already run them through one of the domain checking
sites and posted all the problems.

-- 
Barry Margolin, barmar at genuity.net
Genuity, Woburn, MA
*** DON'T SEND TECHNICAL QUESTIONS DIRECTLY TO ME, post them to newsgroups.
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