If packets for port 465 arrive on eth0 and nothing is sent in response
then we know the following:
1) Your system replies to ARP requests. So there is two-way
communication at the ethetnet layer.
2) Your system does not respond to TCP SYN requests. There is no
two-way communication at the TCP layer.
This suggests the TCP SYN is dropped (firewall problem), or that
your system responds to TCP SYN on a different network interface
(routing problem).
It there any TCP connectivity between the client and the Postfix
server on that specific IP address?
Wietse
