The installation, here, is like millions of others. We are on a private VLAN with the router acting as the gateway to our ISP's network and the internet. There is nothing unusual about that so the question is Can systems on a 192.168.x VLAN use smtp to send mail to each other?
I really should know the answer to this because I am a retired systems engineer who used unix systems and mailers all the time but that was in a university network and I would just assign a DNS name to each box and maybe a MX record if it was necessary so that box1.midlevel.edu could deliver mail to box2.midlevel.edu whether it was across the room or on another continent. The DNS support is what you don't have on a private VLAN so I want to do this in a safe but simple way. This would make it possible for Linux boxes on the network to send messages to the system I normally receive mail on so that squawks about a process crashing or some other problem are sure to be seen. The other systems sending those messages don't even necessarily need to send mail outside the network but they do need to send mail to the system I normally read mail on. I looked up this topic using duckduckgo and found very little hits that were on topic and lots of mercantile buzz about email hosting companies, etc. All are necessary but not what I was asking about. I have put static IP records in to the dhcp server on our router so 192.168.1.xx will always either have a specific host at that address or nothing if the MAC address changes and the record hasn't been updated. Also, I have put /etc/hosts files on Linux systems and a Mac and I believe there is a hosts file one can add to Windows systems for a similar effect. Thanks for any good ideas. Martin McCormick