I’ve been running Sendmail on systems since 1996, so it was a pretty big deal for me to finally move over to Postfix as my MTA of choice. Once I finally made the switch though I was much happier. Overall I found that getting Postfix to do what I wanted was easier than doing the same thing with Sendmail.
Today I noticed the development of completely new version of Sendmail: Sendmail X. On the surface it looks like they are taking many of the same principles used Postfix for this rewrite. Instead of one big process that does everything, they’ve broken it out into modules, some of which will be threaded. There’s a new configuration syntax that reminds me of the Bind 8/9 syntax. Some features are being left out (at least initially), like UUCP, 7 bit MIME conversion and support for dialup systems.
Does anyone still use UUCP? Fortunately I was spared ever having to go through that. I don’t recall where I heard this, but the joke about how to get UUCP working was to find someone else that already had it working and duplicate what they had. I don’t think I’ve ever heard anyone say anything good about UUCP.
There is a huge “Requirements, Architecture, Functional Specification, Implementation, and Performance” document that is chalk full of specification details for Sendmail X if you want to know more. For now I’m going to stay with Postfix.