2 Aug
2013
2 Aug
'13
11:11 a.m.
On Fri, 2 Aug 2013, Nigel Rantor wrote:
Ah, I omitted this on my resolved update.
I had
A otter.wiggly.org -> IP
A mail.wiggly.org -> IP
MX mail.wiggly.org
IP PTR otter.wiggly.org
So when doing a full circle you found that the MX name didn't match the PTR
record for the IP it resolves to.
I fixed this before finding the problem with the SPF / IPv6 issue so I don't
know if it was another problem that required fixing, it is better to have
these the same though so I am leaving it that way and will have to live with
my MX being called "otter" and not "mail".
It doesn't matter. Take GMail for example:
$> dig +short mx gmail.com
20 alt2.gmail-smtp-in.l.google.com.
40 alt4.gmail-smtp-in.l.google.com.
30 alt3.gmail-smtp-in.l.google.com.
10 alt1.gmail-smtp-in.l.google.com.
5 gmail-smtp-in.l.google.com.
$> dig +short a gmail-smtp-in.l.google.com.
173.194.67.27
$> dig +short -x 173.194.67.27
wi-in-f27.1e100.net.
However, what does matter is that if you look up the A record for that
latter domain, that you'll get the IP address back:
$> dig +short a wi-in-f27.1e100.net.
173.194.67.27
216.239.32.27
I think people tend to confuse this with "PTR should match A".
Martijn.