#369105 dnsmasq: setting the A record for the MX desirable

Package:
dnsmasq
Source:
dnsmasq
Submitter:
Martin-Éric Racine
Date:
2010-11-30 22:54:26 UTC
Severity:
wishlist
#369105#5
Date:
2006-05-27 14:52:36 UTC
From:
To:
It would be desirable for dnsmasq to also set the A record for the mail exchange,
to accomodate MTU that are not capable of polling the nameserver for MX records.
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#369105#10
Date:
2006-05-27 15:57:26 UTC
From:
To:
Martin-Éric Racine wrote:
/etc/dnsmasq.conf and corresponding A record in /etc/hosts. The design
of dnsmasq makes it impossible to create answers which contain data from
both the upstream nameservers and local configuration.

Cheers,

Simon.
#369105#15
Date:
2006-05-27 16:50:08 UTC
From:
To:
la, 2006-05-27 kello 16:57 +0100, Simon Kelley kirjoitti:

Doing it that way, MX record can be an FQDN target at the ISP as defined
in dsnmasq.conf (which leaves room open for the ISP to change the IP of
their SMTP host), but A record ends up statically defined in /etc/hosts
(which forces the dnsmasq user to hack /etc/hosts every time their ISP
changes its mind about the IP for their mail server).

What we need is a way to avoid statically linking an IP to the mail
server's A record and to map it dynamically just like the MX answer.
#369105#20
Date:
2006-05-29 09:21:56 UTC
From:
To:
Martin-Éric Racine wrote:
basically no way to create a DNS reply which has some local information
and some from upstream, without completely re-writing the program, and
losing the small footprint.

Have you actually found an MTA which doesn't do a second A record DNS
lookup when it gets an MX record without an additional section?
I can't quickly find an authoritative reference, but I think the absence
of additional section records should not be taken as evidence of absence
of records in the DNS. Addition sections are a performance hack to
eliminate redundant queries, not authoritative answers.

Cheers,

Simon.
#369105#25
Date:
2006-05-29 12:04:08 UTC
From:
To:
ma, 2006-05-29 kello 10:21 +0100, Simon Kelley kirjoitti:
That is, we currently have:

mail.intranet,mail.isp.com,50

We could give an A record reply that is the ISP's mail server IP. We
would end up with:

MX: mail.intranet, which is an alias for mail.isp.com with priority 50.
A: mail.intranet, whose IP is the same as the one for mail.isp.com.

Not quite kosher, I know, but it would achieve the desired result.

ssmtp (debian package of the same name) knows nothing about MX record.
#369105#30
Date:
2006-06-25 16:43:58 UTC
From:
To:
Martin-Éric Racine wrote:

If I've understood you suggestion correctly, you could do that just by
putting the mail.isp.com A record in /etc/hosts. dnsmasq would then
supply the A record in the additional section.

If that's a solution, then I'll probably tag this "wontfix". As a
explained before, the complete solution is not practical.

Ah, OK.

Cheers,

Simon.
#369105#35
Date:
2006-06-25 18:12:39 UTC
From:
To:
su, 2006-06-25 kello 17:43 +0100, Simon Kelley kirjoitti:

That won't work, because /etc/hosts wants static IP addresses, while
what we're trying to achieve here is to dynamically fetch the A Record
the same we we do for the MX Record.