This thread has set me thinking about MTAs, and more specifically why OpenACS uses Qmail. I know that Qmail is deemed to be 'secure' - AFAIK in its lifetime, there has only been one remotely exploitable DoS attack found, and nothing else. But for all its secure architecture and coding, it remains a dog to configure - and as the thread I linked above demonstrates, if it isn't easy to configure, then it opens itself up to new security problems.
I used to use Qmail on my development machine, but I've now switched to Postfix. I admit this is in part due to laziness - on most systems one can run 'emerge postfix', 'rpm -ivh postfix' or whatever, spend a couple of minutes editing the superbly commented configuration file (10:1 comments to config lines ratio) and have it ready for use (I only use it for outgoing, I guess you'd want to spend a little more time if you were receiving too!). I manage live servers running both Qmail and Postfix as MTAs (again outgoing only), and aside from an easily patched bug with AOLServer 3.3 + Postfix, the only difference I noticed was that it took me a few hours to install a system that wasn't transparent with configuration split over several files (and has general wierdness like binaries and configuration stored in /var instead of their standard locations like /usr/bin and /etc) compared to a few minutes to install a system that I felt much more comfortable with and is fully integrated with my system package manager and configuration tools. Even Life with Qmail finds little to distinguish between Postfix and Qmail in terms of security etc.
So my question is this: why is Qmail part of the OpenACS reference platform and not Postfix?
As I see it, there is only one reason at the moment - because it is. Grepping through the code from head shows that there are a few references to Qmail-specific queues and programs in, e.g., notifications, ecommerce, acs-mail-lite, and webmail. However, this thread describes how you can configure ACS to use Postfix instead of Qmail for notification replies, and I can't believe that the other parts of code that require Qmail couldn't be rewritten to support generic MTAs.
My arguments for switching to Postfix would be easier configuration and easier installation. IMO, both these things reduce the complexity of setting up an OpenACS install, and seem as a lot of people gripe about how hard OpenACS is to install (say, just to demo), surely reducing this overhead should be a community objective? Then there's the issue of avoiding misconfigurations that lead to abuse of OpenACS servers.
This subject has been raised before, but that was back in 2000, and four years on, little has changed. Perhaps at a minimum we could offer Postfix as an alternative in the installation guide and cover the caveats that that brings? And how much effort would it take to achieve MTA independence?
I think I've said enough, I'll sit back and await the flames 😊.
