postfix rejecting mail from another postfix server on same network

Hi, I have 2 x debian servers mail.one.com and mail.two.com they both send and receive email fine outside of the local network however mail.one.com can not send mail to a domain on mail.two.com and vice-versa
If I telnet from mail.one.net to mail.two.net 25 it just hangs, same in reverse,
I have added both local and public ip address's to mynetworks
telnetting using the local (192...) network also works fine.

I CAN make it work by adding a domain from mail.one.com to hosts file in mail.two.com (resolving the local network address) but this means I have to do this for each domain on each server and I am sure I should not have to do this... any ideas ? ... it is not a firewall/fail2ban issue, DNS appears to be fine for all domains - it is only server to server email that is not woeking.
Any pointers appreciated.

 

Is the only route between the two mail hosts in the local network? For mail to work they need a route between their public IP -addresses.

 

aha, ok , I can ssh between hosts using local network ip but not via public IP so that makes sense.... they are on some older vmware infrastructure and I assume I will have to do something with the edge gateway... googling now.
Thanks for that ... I was looking for some firewall or postfix issue but I think you are on the right track.