I started using a simple SPF configuration:
deny message = $sender_host_address is not allowed to send mail
from $sender_address_domain
spf = fail
I found that with this in place people using sky.com were unable to send
us mail. sky.com use googlemail to provide their mail service, and the
problem also affected other domains which used googlemail, but not
googlemail.com/gmail.com addresses. The senders were seeing errors like:
Temp_failure. Connection was dropped by remote host. (sent_RCPT)
Nothing was appearing in our logs.
I upgraded to Exim 4.69 but that didn't make any difference. The
problem is reproducible.
Are other people using spf in this way able to receive mail from sky.com?
--
Richard Gilbert
Corporate Information and Computing Services
University of Sheffield, Sheffield, S10 2TN, UK
Phone: +44 114 222 3028 Fax: +44 114 222 3040