[Mimedefang] OT: sendmail limit connections

[Sven Willenberger]

On Fri, 2005-02-25 at 16:43 -0600, -ray wrote:
> On Fri, 25 Feb 2005, Matthew S. Cramer wrote:
> 
> > I implemented months ago and slowly increased the pause up to
> > 1250 ms.  I wanted to avoid any false positives (I have had none) and
> > found that any further increase in the pause doesn't substantially
> > increase the amount of rejections.
> >
> > We hit about 125,000-150,000 rejections due to the pause, per month.
> 
> I upgraded sendmail last night and started with a greet_pause of 5 
> seconds.  I think a legit mailserver can wait 5 seconds for the 
> 220...sometimes dns takes longer than that!  The biggest pain is my access 
> map is in LDAP so i had to remember howto create ldap objects, haha.
> 
> I also added ConnControl limit of 15.  I don't think there's a legit 
> reason for any one host to open more than 15 tcp connections.  Comments?
> 
> ray

Those numbers are about in line with what we use (we see about 2-3
million email delivery attempts or so per day)

Default greet_pause of 5000 ms
ClientConn:  10
ClientRate:  15

Generally these work nice and cause no problems with legitimate mail
delivery. We have exceptions to the list for certain ips of course ....

Sven