secondary MX Server


postfix 3.4.5

i mean i have a correct running postfix server. ;-)

Now I like to create a secondary postfix for my system.

What are the best to realize, have this two servers in sync?

I have enable postscreen, all I found on Internet, is to have installed
memcache is this correct?

But what can / must I sync?

Thanks for a answer,


Re: secondary MX Server

By Viktor Dukhovni at 06/06/2019 - 22:21

On relay servers that don't store mailboxes, you don't really
need to sync anything. Just let them work in parallel. Postfix
is not a mailstore, and synchronizing mailstores is the job of
Dovecot and the like...

Re: secondary MX Server

By =?ISO-8859-1?Q?... at 06/07/2019 - 06:24

Am Freitag, 7. Juni 2019, 04:21:49 CEST schrieb Viktor Dukhovni:
The second MX shout have also dovecot and all the Mails that is clear?

Re: secondary MX Server

By Wietse Venema at 06/07/2019 - 08:06

G?nther J. Niederwimmer:
No. Secondary MXes forward email to primary MXes.

If you want something else, don't call it secondary MX. That
term already has common usage.

RFC 5321

A relay SMTP server is usually the target of a DNS MX record that
designates it, rather than the final delivery system. The relay
server may accept or reject the task of relaying the mail in the same
way it accepts or rejects mail for a local user. If it accepts the
task, it then becomes an SMTP client, establishes a transmission
channel to the next SMTP server specified in the DNS (according to
the rules in Section 5), and sends it the mail.


Re: secondary MX Server

By Matus UHLAR - f... at 06/07/2019 - 06:38

On 07.06.19 12:24, G√ľnther J. Niederwimmer wrote:
this is oustide of postfix's scope. if you need two separate mail storages,
with data synchronization between them, you need to do it on another level,
not on postfix level.

Re: secondary MX Server

By Durga Prasad Malyala at 06/06/2019 - 23:10

On Fri, Jun 7, 2019, 08:05 Viktor Dukhovni <postfix- ... at dukhovni dot org>

Pls see this!topic/mailing.postfix.users/hUlPvJaRJI4

Re: secondary MX Server

By =?ISO-8859-1?Q?... at 06/07/2019 - 06:26

Am Freitag, 7. Juni 2019, 05:10:09 CEST schrieb Durga Prasad Malyala:
Thank's for the Link but this have I found ;-)