Michael Heydon <michaelh@???> wrote:
> Why is all this messing about necessary?
Because otherwise you won't deliver email.
> Our mail servers have hostnames that aren't in external DNS, I just have
> "primary_hostname = mail.jaswin.com.au" and that is what they claim to
> be when talking to the outside.
Someone else has added this to your external DNS, then, because I can
see it:
dig any mail.jaswin.com.au
;; ANSWER SECTION:
mail.jaswin.com.au. 86400 IN A 61.88.158.22
;; AUTHORITY SECTION:
jaswin.com.au. 86400 IN NS ns2.optusnet.com.au.
jaswin.com.au. 86400 IN NS ns1.optusnet.com.au.
And
dig +short -x 61.88.158.22
jaswin.com.au.
But
dig +short jaswin.com.au
203.2.75.99
You're lucky it's working at the moment. You really ought to try and
get some correspondence between your forward and reverse DNS
entries. (Change the rDNS for 61.88.158.22 to mail.jaswin.com.au if
you can.)
Chris