Rodney Baker said the following on 10/25/2008 10:18 AM:
Pardon me for butting in, but my understanding is that local delivery of mail is the job of the MDA (mail *delivery* agent) not the MTA (mail *transfer* agent).
Sendmail is not an MDA - it does not deliver local mail to a user's mailbox. It is designed to transfer mail between hosts. Local delivery is the job of something like procmail.
*sigh* I wish it were as simple and well partitioned as that! Postfix, as well as the old sendmail, qmail, Smail3, ZMailer and others, is capable of local delivery as well. Having Postfix pipe ail for local delivery though procmail is very sensible and offers a great deal of per user controllability. I have my Postfix->procmail(user) on my mail hub bypass via a whitelist, and put mail in the correct folders, and run the rest through spamassassin. Along the way I have a blacklist, some of it from spamassassin, that procmail pipes back to Postfix. Some of the back-feed is to spam analysis sites and some of it simply bounces.
Postfix and Exim, as I understand, include both MTA and MDA functionality. I agree - you do need to have an MDA running to locally delivery user's mail to their mailboxes, unless the users are solely accessing an external mailserver via POP3, IMAP or the like using a client such as Kmail, Evolution etc. in which case no local MDA is needed, *unless* the user also wants to receive adminstrative emails from the local machine that are normally directed to root.
And there we get to the point of the original discussion. (From which we've diverged too much!) Given that many installed packages use mail rather than syslog ... Oh, why should they? Well mail forces delivery, syslog doesn't. ... either this is an enterprise setting with IT support to take care of configuration, in which case we wouldn't be having this discussion, or its a small home system. If the latter its either a sophisticated user such as Per, Carlos, yourself or myself, or its Joe AverageUser or his parents or grandparents. If its a sophisticated user, then we can hack things whatever way we choose, and that's not what I'm interested in or the point I'm trying to make. So Joe (or...) has this Linux, possibly form a LiveCD so he cold kick the tires without committing himself, and its really to avoid the Windows Tax. He's running a GUI, reads mail via Gmail, browses the web, downloads his camera writes a few letters, does a bit of accounting with a spreadsheet. He doesn't want to know what's "under the hood" any more than with his cell phone (which, coincidently runs an embedded version of Linux! but he doesn't know that), his fridge or his mp3 player.
My understanding of the original poster of this thread was concerned that sendmail/Postfix/Exim were dependencies that *could not be uninstalled without breaking the system to the point of unusability* - the concern was that since his machine was either stand-alone or client-only and was very limited on disk space, that these services should be able to be uninstalled (or not installed in the first place) without breaking the whole system.
Actually I can see a number of ways that the system can become brittle or perhaps eventually 'break' even if they are installed. The way my system was installed from a LiveCD (not an upgrade of a previous, just blow away everything except the /home partition) was like that. If the installation is into one partition - the way things are usually with MS-Windows - it become VERY brittle and insecure.
In that regard, I tend to agree. Forget the enterprise or other scenarios - this is solely regarding the case of a minimal install on a resource-limited client machine that has absolutely no need for an MTA to be installed. Even client software such as Kmail/Evolution/Thunderbird can send via an external mail server.
:-) And more to the point, while all those *can* access local files, the user has to know and set it up to do so. No wonder people are returning the Linux netbooks; Linux as is takes too much set-up. The old accusation that UNIX was written by geeks for geeks seems to be true in trumps for Linux. -- The real distinction is between those who adapt their purposes to reality and those who seek to mould reality in the light of their purposes. Henry Kissinger -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org