[Dovecot] More fine-grained connection limitations?

[Joseph Tam]

> There is the mail_max_userip_connections setting, which helps for
> dealing with number of connections at any given time, but I'm looking
> for something that will help deal with users who configure their mail
> clients to connect too frequently.
>
> ...
>
> It would be really great if there were a way to tarpit those users to
> slow them down, or send them an imap message saying they are connecting
> to often and connections have been disabled for the next 5 minutes or
> something.

There might be an unintended consequence: I see connection spikes when
users try to do a global string search across mailboxes.

Joseph Tam <jtam.home at gmail.com>