Mailbox & Server Down

[Nicholas Taylor]

Fetchmail connects to your provider's e-mail server as if it were an 
MUA, then feeds mail to your server's MTA as if it were a peer MTA.  If 
your provider doesn't allow client connections (by IMAP or POP), then 
you're right that fetchmail won't help.

It sounds as though you need to set up some kind of failover for your 
MTA: a second SMTP server, probably configured to feed your primary SMTP 
server (which then feeds mails to dovecot), but with a very long queue 
and many retry attempts.  Then set your Internet-facing router to direct 
SMTP connections to your primary SMTP server (if it's up), falling back 
to your secondary server if the primary is down.

That's not really a dovecot problem: dovecot replication solves the 
problem "I cannot read my e-mail when my IMAP server is down" [1], and I 
think the problem you want to solve is "My provider throws away e-mail 
when my SMTP server is down"?

[1] And load management, and backup, and probably other stuff, none of 
which is relevant here.

Nick

On 04/06/2020 06:13, Andrea Miconi wrote:
> I read about fetchmail.
> I understand that it doesn't work if the mail server uses an MTA.
> 
> 
> 
> Il mercoledì 3 giugno 2020, 15:07:51 CEST, Nicholas Taylor 
> <net20 at cam.ac.uk> ha scritto:
> 
> 
> This is pretty much exactly what I do.  I use fetchmail [1] to download
> mail from my ISP and feed it to exim, which delivers everything to
> dovecot.  I don't know whether it's possible to configure dovecot alone
> for this.
> 
> [1] It's horrible, but it worked in 2007 and I'm intensely lazy.
> 
> Nick
>