> On Apr 29, 2018, at 3:37 AM, Dominic Raferd <domi...@timedicer.co.uk> wrote:
>
> This is a genuine and expected sender (VoIP provider). I am less sure
> about atlas.net.tr, but it is probably genuine and expected by
> recipient too. Unwanted ones I have not bothered to report here.
>
> I don't require encryption on port 25: smtpd_tls_security_level = may
If you have time to look into this further, you need full-packet
capture PCAP files.
# set -- 192.0.2.1 192.0.2.2 # season to taste
# filter=; for ip
do
[ -n "$filter" ] && filter="$filter or "
filter="${filter}tcp host $ip"
done
# tcpdump -s0 -w /var/tmp/tls.pcap $filter
--
Viktor.
