how nginx can improve imap webaccess

[Brice Figureau]

Hi,

On Mon, 2007-11-05 at 15:14 +0000, Alain Spineux wrote:
> I looked for long information about how nginx can improve IMAP !
> After hour I found this useful remark from Igor on this list:
> 
>   You need nginx IMAP/POP3 proxy only if
> 
>   1) you have several IMAP/POP3 backends,
>   2) you need the single enter point, say, mail.domain.com,
>   3) and you have a LOT of IMAP/POP3 accounts (e.g. as
>      fastmail.fm: http://blog.fastmail.fm/?p=592 )
> 
> 
> I was expecting nginx was able to filter login/logout command
> needed by "connection less" request from web client!
> But it doesnt happend !

Because it wasn't designed to do that. It was designed to spread the
load of tons of IMAP clients to several upstream IMAP servers.

> Then my question ! Can nginx improve IMAP web client accesses ?

I don't think so, since nginx doesn't support connection caching, and
webmail issue is that the connections from the web server to the imap
server are restarted on each web browser request.

> I know IMAP protocol, and I don't see myself how to could be easy to cache
> status or LIST result, this why I ask.

I think you should have a look to UP-imapproxy:
http://freshmeat.net/projects/imapproxy/
http://www.imapproxy.org/ (which wasn't responding this morning)

It has been designed to cache the connections from the web server to the
imap server.

Hope that helps,
-- 
Brice Figureau <brice+nginx at daysofwonder.com>