Hi , Obarthelemy
In post 1, you say "I want to send myself status messages without going through my ISP". (very frankly, that does not really require mail: have your plug post a log to a shared directory, and poll the log from your main PC)
Never thought of that, What I was originally trying to achieve was like I with the Linkstation pro which would send me a nightly report on disk status etc, but instead of it sending the message to my isp mailbox , which I would have to collect back, I wanted to collect the mail direct.
Since then thing have moved on a little, I have installed Dovecot as my e-mail pop3/? Server and Postfix as my smtp server.
So I guess all I need to do is collect the mail off my isp and deliver it to me.
In post 2 you say "I want to pull my mail to the Plug, then serve it from there". That is a classic Mail server: you need SMTP to send mail, and POP or IMAP to receive. IMAP is more flexible, ie it lets you , optionally, sync your mail both ways (deletions/moves on the client also get deleted/moved on the server), while POP is dumber (gets the mails, and that's it, no back sync). Unless you have specific needs, such a setup sounds way overkill though: you end up with your mail in 3 places (remote server, Plug, client), which opens the door for lots a fun (for example if the 3 mailstores get de-synched while you're on a trip), for little or no purpose I can see (there are much easier ways to do backups).
IMAP ? , never played with IMAP , so may have to try to get it working after I`ve sorted POPs out.
In the end, it`s just learning what a plug will do, and finding a good use for it, But agree with it been overkill.
I`ve needed it !!!!, looking in the logs and finding errors why it wasn`t working, fixing that error and just getting a new error which I have to google my way out of.