[ZendTo] {SPAM?} Re: Issues with sending to external users

[Mike Brudenell]

On 13 January 2017 at 16:24, Jules <Jules at zend.to> wrote:

> And as you were sending via IPv6, and utoronto.ca's SPF record does not
> contain *any* IPv6 statements at all, then Google will block all IPv6 mail
> traffic from utoronto.ca (regardless of whether it comes from your ZendTo
> server or your university's central outgoing mail servers).
>

Not quite… The utoronto.ca SPF record ends with "~all" rather than "-all".
This indicates only a "softfail" for unlisted hosts that, according to the
RFC, means

A "softfail" result is a weak statement by the publishing ADMD that the
host is probably not authorized.  It has not published a stronger, more
definitive policy that results in a "fail".



If utoronto.ca has any IPv6 network in place (which they appear to, as you
> could get to Google via IPv6), then they really should add an IPv6
> statement to their SPF record. Or else no-one is going to want to receive
> any IPv6 mail they send.
>

It could be that, like ours here, their mail gateways aren't yet IPv6
capable in which case the SPF record would be OK (although I'd have hoped
their Firewall would have blocked other hosts from sending email out). Also
I *think* we're still only assuming the sending domain is utoronto.ca: I
don't recall seeing an unobfuscated set of details.

But there's certainly quite a few things in this area Brian needs to
investigate!

Cheers,
Mike B-)

-- 
Systems Administrator & Change Manager
IT Services, University of York, Heslington, York YO10 5DD, UK
Tel: +44-(0)1904-323811

Web: www.york.ac.uk/it-services
Disclaimer: www.york.ac.uk/docs/disclaimer/email.htm
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mailman.ecs.soton.ac.uk/pipermail/zendto/attachments/20170116/1a296a2b/attachment.html