Mailbox & Server Down

[Stefan Hagen]

Andrea Miconi wrote:
> My mailboxes are on a Dovecot (IMAP) server.
> On DNS there is an MX record pointing to the server.
> To read the mail I use Roundcube.
> If the server is down, I lose the new mail.

Really? What kind of downtime makes you loose emails?

If your server is down, mail delivery is tried every couple of hours for
days. So - if your server is down for a day or two, no email should get
lost.

You might loose a couple of spam mails, as they don't do retries for
performance reasons, but every halfway correctly configured MTA these
days is doing this properly.

It can take some time until all emails arrive after the server comes
online again. If this is an issue or if you need something more
professional for a business environemnt, then configure a second MX with
the same SMTP and dovecot configuration, then configure replication
between the two dovecot instances. https://wiki.dovecot.org/Replication

HTTP is another topic. If you also need high availibilty of your
roundcube frontend, then you'd need a reverse proxy/load balancer in
front of your server that can detect the outage and then direct the user
to the other frontend on the second MX.

HTH,
Stefan

PS: The text part in you email is broken (no line breaks).