I can't connect to any of the IP addresses of cluster8.eu.messagelabs.com (e.g. 216.82.251.39) for mail delivery via port 25 for many days.
Postfix receives a timeout and any TCP connection times out.
The source IP of our mail server is 78.47.9.251 (mail.itbt.it) and it is not listed on any blacklist nor has any bad reputation marks on http://ipremoval.sms.symantec.com/lookup/
TCP connections from IP addresses within the same subnet (e.g. 78.47.9.252) are possible for connecting port 25/tcp and ICMP ping response packets are replied with an ICMP reply.
Though it seems all IP addresses of cluster8.eu.messagelabs.com are blocking incoming connection to port 25 from 78.47.9.251.
Could you please help me, with this problem? Pretty please.
Kind regards,
Loris
