The end of Dovecot Director?

[hi at zakaria.website]

On 2022-10-21 06:19, Zhang Huangbin wrote:
>> On Oct 21, 2022, at 4:19 AM, Antonio Leding <tech at leding.net> wrote:
>> 
>> My understanding is that Director is targeted toward large enterprise 
>> mail installations that will incorporate several servers for a given 
>> function. In such an environment, Director would be the 
>> fore-person\traffic-cop keeping things organized & squared-away.
> 
> Director is used when you setup frontend servers in a load-balance 
> cluster, proxy imap/pop3/lmtp/managesieve requests to backend Dovecot 
> servers.
> 
> I setup load-balance cluster for clients with HAProxy + KeepAlived + 
> Dovecot Director running in frontend servers, so sad we have to find an 
> alternative to replace Director in such case.
> 
> It's not about "small/medium" servers, but the demand of imap/pop3/lmtp 
> proxy service, especially in load-balance cluster.
> 
> ----
> Zhang Huangbin, founder of:
> - iRedMail: Open source email server solution: 
> https://www.iredmail.org/
> - Spider: Lightweight, on-premises Email Archiving Software: 
> https://spiderd.io

Hi,

I was wondering if one can achieve the same implementation with haproxy 
without dovecot director? Load balancing all requests to pop3, imap, 
managesieve and lmtp services from specified frontend servers i.e. 
webmail to specified backend servers and using NFS mount 
filesystem/syncing data across all servers to access emails with high 
availability?

Not sure whats the big deal director is offering? Is it just a native 
functionality providing a feature to find which backend server have X 
emails available and chooses to load from e.g. its content i.e. like 
checks which first server that doesnt return http 404 response 
equivalent in IMAP/POP3/LMTP/ManageSieve?

Sometime ago I used Varnish caching directors to implement high 
availability using 404 response status in http web server, and it seems 
great if we can have this feature in dovecot too, as it offers high 
availability with delayed-syncing/partial-syncing across unknown 
selected servers, I managed to use Varnish too in dovecot proxy service 
i.e. the webmail, yet it requires NFS mount or high available file 
system all servers can have through immediate access to e.g. maildir?

Any helpful input that would clear the picture for me in regards dovecot 
director, would be ver much appreciated.

With thanks.

Zakaria.