[Dovecot] Meaning of mail_max_userip_connections?

[Harald Strack]

Hi Timo, 

On Mon, 2010-09-27 at 13:50 +0100, Timo Sirainen wrote: 
> On Mon, 2010-09-27 at 12:17 +0200, Harald Strack wrote:
> > > > Our users mostly accessing the IMAP server by a webmailer or  proxies.
> > > > Thus, all users (>10000) come from only 5 different IP. However, I got a
> > > > lot of complaints about denied connections after setting
> > > > mail_max_userip_connections = 10.
> > > > 
> > We want to limit the number of imap processes per user to 10, but not
> > the number of processes per client IP (because of the proxies).
> 
> For that mail_max_userip_connections should have worked. If you get
> complaints then it's because some client opens more than 10 connections
> (or user has multiple clients open from same IP) or your webmail opens
> >10 connections simultaneously.
Accordingly, mail_max_userip_connections limits the number of
connections from an IP. To deal with a scenario, when 400 Users behind a
NAT-gateway come from the same IP (the gateway), we have to set
mail_max_userip_connections = 400, right? 
> 
> You didn't say if the complains were from webmail users or from IMAP
> client users.. Assuming webmail, I guess the problem is that it just
> opens so many connections. 
Both. 
> With v2.0 you could specify different limits
> to a certain network range (i.e. disable it for webmail, keep it for
> rest).
Will there also be a limit per user? 
> 
> BTW. The default for mail_max_userip_connections is 10, so do you mean
> before you had it set to 0?
Nearly. We had it set to 1000 and we set it to 1000 again now.

best regards

Harry