Dovecot versus Postfix

[Rashkae]

Jan Sneep wrote:
>> It sounds like you may have it configured already -- just use it!
> 
> That's precisely the problem, can't find any document or anyone who can tell
> me HOW to use it !
> 
> Lot's and lots on how to configure a multitude of settings, but NOTHING that
> says "Now, to use this server all you have to do is ...."
> 

To use Postfis:

configure a mail client to send e-mails either through smtp: localhost

Or, some unix only mail systems (like Mutt or Evolution) can simply pipe 
outgoing e-mail to sendmail program.  I suggest using a different e-mail 
program than your usual one to test and play with the configuration. 
Note: when you have postfix installed, it creates a symlink from 
sendmail to postfix, so programs that call sendmail directly will work 
with postfix.

If you want to send e-mail to a local user, send it to 
username at localhost  As you already discovered, that won't work if your 
e-mail program is forwarding e-mail to your ISP's smtp server, so use 
your own.

To make life complicated, some ISP's block port 25, which means you will 
no be able to send e-mail from your own smtp server to others on the 
Internet directly.  And if that weren't annoying enough, some small time 
e-mail servers try to control spam by not accepting e-mails sent from 
dynammic IP's.  To get around these, you have to configure postfix on 
your system to forward any outgoing e-mails to your ISP smtp server. 
This is called a 'smarthost' configuration.  I believe debian (and 
Ubuntu) allows basic smarthost configuration through the the 
dpkg-reconfigure postfix command.

Ok, once you've gone this far, you want to be able to see all these 
e-mails you've been sending your local users.

Open your favorite test e-mail client, and add an account, type Imap, 
server is localhost, and use Secure SSL Imap (default port of 993).

I know that using encryption to talk to localhost seems like a waste, 
but I think by default, dovecot only enables encrypted communication.

When your e-mail client opens the new account, you should be able to see 
all the e-mails you've sent to that user at localhost.

Once you have all this working, if you want to extend the services to 
the other hosts in your network, assuming you have a small enough 
network that it's not worth the bother setting up DNS and what not.... 
(Note, you will have to give postfix a hostname so it knows which e-mail 
it needs to deliver to local users.  You will also have to cofigure 
postfix so it can relay mail from your local network)

If it doesn't already, give your server a static IP address rather than 
using DHCP.  The static address you choose should be outside the range 
used by your router DHCP server. (Most routers I've seen start at 100, 
so, for example, if your normal IP is something like 192.168.1.101, you 
can safely assign 192.168.1.2 as your server IP, Never use address 
ending with .1, that's almost always used by the router itself)

Now when you configure the e-mail clients on other stations of your home 
network, use smtp 192.168.1.2 (from my example) for outgoing e-mail, and 
add an IMAP account to 192.168.1.2 so they can receive any locally 
generated mail.

I'm sorry I'm not including any step by step for any of this, but I 
figure for now, what you need is an overview/roadmap of what needs be 
done.  Now you can pursue documentation for these software servers and 
ask targetted questions for any of the steps.