for long time Microsoft Exchange users who run their own email server, this is the end of the era. Old homelab enthusiast retired Exchange after 27 years of usage. This is the end of an era for self hosted exchange systems. Such event is an indication of increasing pressure on individuals to leave on-premise legacy systems behind in favour of managed cloud solutions.
Enthusiast migrates final on-premises relay to Ubuntu Postfix after 27 years
Meta4X user was running Exchange 5.5 since 1999. Upgraded all the way through all the big releases until Exchange 2019. With recent introduction of Exchange Server Subscription Edition, licensing has become complicated for small usage users.
Now it is only relay server for the on premise system. Mailboxes moved to Microsoft 365 years ago.
Now user is moving away from old on premise server to Postfix (Ubuntu Server LTS) for email relay. User will be able to implement STARTTLS encryption and Let's Encrypt certificates for secured communication. Also planning boot encryption to secure new system even more.
Moving forward has been presented by user as a chance to get rid of all the technical debt they've been piling on for last 20+ years. For example, Exchange 2019 end of support was a big trigger for them to decommission on premise relay system. Improvements are planned, although it is not known if new postfix setup is already in place or not as per source.



Twenty seven years is a lifetime in IT. I still have my first Exchange 5.5 tape drive gathering dust in the closet.
The subscription model for Exchange 2019 is just a way to force upgrades. Good riddance to the technical debt.