h2n utility

[Eddy Kalem]

Ahh! I see now...that makes sense. I never really had to use the h2n utility
until now, so I was used to adding records manually and I never added the
extra MX record.

Thanks,

Eddy

-----Original Message-----
From: Kevin Darcy [mailto:kcd at daimlerchrysler.com]
Sent: Thursday, January 27, 2000 3:44 PM
To: 'bind-users at isc.org'
Subject: Re: h2n utility


Eddy Kalem wrote:

> I noticed that when I run the h2n utility it generates an MX record for
> every A record. Does this have to be or am I doing something wrong?

I suspect that this was done deliberately as an optimization: if a mail
server does an MX record query and gets no answers, it then has to do an
A record query. That's two queries. But if every A record automagically
has an accompanying MX record, then it only has to do the MX query (the A
record is then typically supplied in the "additional" section of the
response), and the total number of queries is cut in half. In theory. More
recent versions of sendmail deal with the problem by doing an ANY query,
thus obtaining both types of records, but older versions, or other
mailers, may still be using the old-fashioned method.

According to the h2n documentation, you can suppress the MX record
generation with the -M option.


- Kevin