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<div dir="ltr" data-setdir="false"><div><span style="color: rgb(38, 40, 42); font-family: Helvetica Neue, Helvetica, Arial, sans-serif;">> If your server is down, mail delivery is tried every couple of hours for</span><br clear="none" style="color: rgb(38, 40, 42); font-family: Helvetica Neue, Helvetica, Arial, sans-serif;"><span style="color: rgb(38, 40, 42); font-family: Helvetica Neue, Helvetica, Arial, sans-serif;">> days. So - if your server is down for a day or two, no email should get</span><br clear="none" style="color: rgb(38, 40, 42); font-family: Helvetica Neue, Helvetica, Arial, sans-serif;"><span style="color: rgb(38, 40, 42); font-family: Helvetica Neue, Helvetica, Arial, sans-serif;">> lost.</span><br clear="none" style="color: rgb(38, 40, 42); font-family: Helvetica Neue, Helvetica, Arial, sans-serif;"></div></div><div><span style="color: rgb(38, 40, 42);"><br></span></div><div dir="ltr" data-setdir="false"><div><div>Fortunately the server went down very few times, but the last one lasted almost two days</div><div>and I lost a lot of mail on multiple mailboxes.</div><div>Even though I work alone, it is still a business server and I can't afford these things.</div></div></div><div><span style="color: rgb(38, 40, 42);"><br></span></div><div dir="ltr" data-setdir="false"><div><div>> then configure a second MX with</div><div>> the same SMTP and dovecot configuration, then configure replication</div><div>> between the two dovecot instances. https://wiki.dovecot.org/Replication</div></div></div><div><span style="color: rgb(38, 40, 42);"><br></span></div><div dir="ltr" data-setdir="false"><div>I had read this page on replication, but I didn't understand how I can access the second server.</div><div>Roundcube/Thunderbird are configured to access an IMAP / SMTP server that matches</div><div>their respective IP addresses, but here the IPs would become 2x2 = 4</div></div><div><span style="color: rgb(38, 40, 42);"><br></span></div><div dir="ltr" data-setdir="false"><div><div>>HTTP is another topic. If you also need high availibilty of your</div><div>> roundcube frontend, then you'd need a reverse proxy/load balancer in</div><div>> front of your server that can detect the outage and then direct the user</div><div>> to the other frontend on the second MX.</div></div><div><br></div><div dir="ltr" data-setdir="false"><div><div>I already have Nginx as Reverse Proxy for Apache on my server.</div><div>However, if I understand your suggestion, I should install a third server for this purpose only.</div><div>Isn't there a guide to refer to?</div><div>I wouldn't even know what to look for on Google?</div></div><div><br></div><div>> PS: The text part in you email is broken (no line breaks).</div><div><div dir="ltr" data-setdir="false"><div><div>I do not understand.</div><div>I am writing from the yahoo webmail.</div></div><br></div></div><br></div><div dir="ltr" data-setdir="false">Many thanks</div><div dir="ltr" data-setdir="false">A.</div></div></div></body></html>