I am trying to setup the following, and I have made some progress. Here's my setup.

• Fetchmail (downloads from my gmail account)
• Mutt (I need to recompile it to use an encryption plugin and compression for email)
• Evolution (Reads mail that Fetchmail downloads, and needs to be able to use Postfix for sending emais)
• Procmail (Sorts my email with regular expressions and prints certain emails, I also need to set it up in conjunction with Spam Assassin)
• Fetchyahoo (downloads emails from my yahoo account because pop3 access is not free for those who sign up with and choose usa as their country)
• Mailman (I'm still trying to figure out what I am going to use this for, but I think it would be very cool and useful to learn.)
• Postfix (smtp server for relaying mail to a smarthost.)

Here are my questions.

1. How can I know if I need SASL when setting up Postfix?
2. How can I know if I need SMTP Authentication?
3. Do I need it because gmail uses it even though I will be relaying mails to my internet
4. Should I configure Postfix to use mbox or Maildir format?
5. Why should I configure it to use one or the other?
6. Does Fetchmail use mbox or Maildir?
7. Which one does it use by default?
8. Should I configure Postfix to use the same as Fetchmail?

Hi fakie flip, I'm not going to give all the answers but you just might be a bit more elucidated.

1. SASL is used to do authentications, so if you want to use this type of auth you must use. In either case there is no problem in setting postfix to also use it.
2. SMTP authentication is nowadays a must have, so YES you SHOULD have SMTP authentication.
3. your INTERNET provider should also need authentication server your server in order to allow the relaying.
4. Maildir and MBox are just tow type of repositories for your mail messages, in my case I use an IMAP server (cyrus-imap) to store mail mail into a DB.
5. your favorite!
6. Fetchmail will retrieve the mail messages from the original server and drop them into your server, using fetchmail you can also rewrite the message recipient.
7. NONE!!
8. I can't really understand your question, but I think you're asking if you need to setup Postfix with the same email addresses you have on gmail,yahoo, etc... No you don't need to do this, as I said before you rewrite the destination address in Fetchmail, this way you can have 3 or 4 different external mail accounts delivering to 1 single internal account.

Hope this can clarify a bit.

JdogPC