On 12/25/2017 12:31 AM, vonProteus wrote:
With one is better and why do you think so? I’m going to chose one and would like to know your opinion
Interesting you should ask this on the Postfix mailing list. Especially since because there is no "right" answer.
Over the years, I've worked with sendmail/procmail, Postfix, Exim, and Qmail. The reason is that I worked at a web hosting company that bought into Web products that featured customer control panels, and the various control panel systems used these mailers as part of their "total package".
Sendmail is just plain cryptic. In response to my complaint about the complexity of the sendmail configurtion file, I was presented with a copy of O'Reilly's sendmail book with this inscription: "It's not that hard" -- Eric Allman. In my library I have books for all the mail daemons...and the sendmail shelf space is larger then other three *combined*.
Qmail is a Dr. Dan Bernstein (University of Illinois at Chicago) creation. As such, it's focused on security (the goad for it's birth in 1997). Instead of having one large configuration file, it breaks up configuration into a bunch of small files. In my mind, this mindset makes saving the state of the mailer a daunting task, as well as needing a rather complex "cheat sheet" to know where to find things. (As an aside, the Unix utility ptx(1) proved extremely useful -- look it up.)
Exim is the baby of Philip Hazel, University of Cambridge (England). It's been awhile since I have approached Exim, but what I do recall is that I didn't like the feel of it. (This is probably just me, not a knock on the daemon.) The configuration is contained in a single file, separated into sections. My one excursion into Exim was to configure it to smart-host all mail through a edge MTA to throttle flow to specific endpoints (AOL, HotMail, Google, and so forth -- and the edge MTA was Postfix!)
Postfix is the product of Wietse Venema (IBM Research). When I was the first customer of DSL in northern Nevada, I was stuck with Pacific Telesys as my e-mail provider. After finding many of my e-mails blocked because of PacTel's reputation, I set up my own mail server. Of the options available, I picked PostFix...and haven't regretted that choice. Postfix uses a pair of configuration files, plus a number of small databases.
There are other MTAs available, but they cost $$$$$$$$. Like Microsoft Exchange. 'Nuff said.
Then there are other opinions:
https://www.tecmint.com/best-mail-transfer-agents-mta-for-linux/ https://en.wikipedia.org/wiki/Comparison_of_mail_servers
Assume for the moment I dismiss sendmail and the non-free MTAs as possibilities. Of the remaining three daemons, it's hard to choose which one is "better". It boils down to a matter of taste, and your needs. All three of the options have their grounding in academia, Exim and Qmail more so than Postfix. All three have regular updates, including security updates. All three have vibrant user communities.
In my networks and at my customers' sites, I run Postfix with Dovecot. This may indeed be the result of "baby duck syndrome", because it was the option I picked as most readily available to me with Red Hat Linux 5 (vice Sendmail) 'way back in the Dark Ages. Postfix was my choice at a web hosting company as the edge MTA when I was fighting blocklists and large mail operators and having to deal with a ton of spam. (N.B.: it helps to know Perl or Python to code custom filters, if you need them.)
My suggestion: take a look at the on-line documentation for each program, or go to a well-stocked library and leaf through the O'Reilly and Que books for each...and "for Dummies" books if you find 'em. (Thank you, Mac McCarthy, for starting that imprint.) Then decide which ones fits you and your needs best.
