[SLL] mailhub relay without knowing accounts and throttling inbound by domain name and outbound with postfix?

[Jeremy C. Reed]

On Thu, 21 Feb 2008, Bill Campbell wrote:

> On Thu, Feb 21, 2008, Jeremy C. Reed wrote:
> >I provide a mailhub (which does greylisting and more).
> >
> >I don't know the accounts for the target systems. I don't control the 
> >target final mail destinations.
> >
> >Sometimes I get many queued emails that are "deferred (delivery 
> >temporarily suspended" because "Error: too many connections from" 
> >(my mailhub).
> >
> 
> I would look at the smtpd_client_connection_count_limit and
> smtpd_client_connection_rate_limit settings in the main.cf file.

I don't have control of the target mail servers.

As for my incoming emails, "Not enough connections from the same remote 
host to really block on client connection rates (without limiting good 
traffic)."

I want to:

- do similar to the  smtpd_client_.*_limit but for throttling outbound 
emails.

- limiting how many target a specific domain in a set amount of 
time (as I can have a good idea what is acceptable). Like 
smtpd_client_recipient_rate_limit but not specific to one client and keep 
track of @domain. For example (made up):

smtpd_domain_recipient_rate_limit = foo.bar:10
(or make that a map with information in a file)

to only allow 10 emails to @foo.bar during the time unit (60s).