Thank you all for the replies.... 

I have the test environment with the same configuration. But I have been asked to go with same environment for HA/Resilience in Live.

Yes, I have only one Live server. It is configured in "Maildir" format. The data stores on a Network / Shared Storage (But definitely not local disk, its a mount point).

I have been asked to create a HA/Resilience for this environment. They gave me another server with same ram/cpu/os and I need to configure the dovecot on it.

Please provide your suggestions/steps as I am new to this kind of environment.

Is it possible, when any email comes to any one or both of the two servers, how it will be read by the user from Outlook? How to create the environment? 

Thanks,

Kishore Potnuru

On Fri, Jan 10, 2020 at 7:55 AM Sami Ketola <sami.ketola@dovecot.fi> wrote:

> On 10 Jan 2020, at 9.20, Emmanuel Dreyfus <manu@netbsd.org> wrote:
>
> On Fri, Jan 10, 2020 at 09:07:24AM +0200, Aki Tuomi wrote:
>> Replication is not supported with mbox. Most features are not.
>
> It would be nice if the document about replication could tell
> what setup works.


First step in setting up HA system would be to migrate away from mbox.

Sami