On 04/08/2024 10:54, Dale wrote:
I've read about people pulling their hair out trying to set up email software and it sounds like a nightmare and they know more about it than I do. I'd like to do this but I'd need a good howto.
Thing is, there's too many jobs required to process email, and in line with Unix's "do one thing and do it well", there are a whole bunch of options at every layer. So let's start at the top ...
Your "sorting office" is managed by postfix/exim/sendmail. That is supposed to be configured such that they transfer mail between themselves on port 25 (the big lorries). They store the mail in /var (the mail delivery office).
Then because configuring the sorting office can be such a pita, there's a whole bunch of programs (fetchmail et al) which ferry small amounts of mail around. They'll go to the upstream sorting office (eg gmail), collect mail from their delivery office front desk, and deliver it to your local postoffice, whether the sorting office or delivery office is down to you.
Now you need your delivery office front desk. That can be dovecot, courier-imap, whatever. It checks the customer (mail client) is who they say they are, collects their mail from the delivery office (/var), and either hands the mail over (POP3), or gives them a copy (IMAP).
Your mail client (thunderbird, mutt, whatever) now caches all your mail locally. If you're using POP, that cache is the only copy. If you're using IMAP, the master copy is still in /var, and you can go and get another copy if you need to.
Okay, that's the basics. But you notice I said you're *supposed* to use postfix/exim/sendmail to bulk transfer mail between sorting offices, however a lot of people use fe5tchmai instead? And I use Thunderbird - collecting mail from upstream and moving to my local downstream. All thoroughly confusing. And fetchmail can skip the downstream postoffice entirely, moving mail straight from upstream into the mail client's cache, just like POP ... indeed I think that was the original design...
And when you're puzzled the "Rest Of the World" doesn't seem to be like that, remember that most people now on Windows just run a mail client, and use upstream as their *local* post office. 'nix expects you to run a post office on your local machine, which I don't think Windows has ever done.
Cheers, Wol
