[Mimedefang] New Sober version bringing MD to its knees?

David F. Skoll dfs at roaringpenguin.com
Fri Nov 25 12:43:11 EST 2005

Fernando Gleiser wrote:

> It worked flawlessly until the last version of sober hit it a couple of
> days ago. Since then that piece of cr*p is hitting it with bursts
> where the server gets 60+ mails in less than 10seconds, so MD runs out
> of slaves.

You might want to set the ConnectionRateThrottle parameter in Sendmail
(confCONNECTION_RATE_THROTTLE in sendmail.mc) quite low, like to around 3.
That delays connections if more than 3/second come in.  While it
still doesn't really prevent the DoS, it can smooth the load on the machine.
Or you can use Sendmail 8.13's more fine-grained rate_control features so
that any one IP address can't open too many connections too quickly.

But your solution of blocking offending IPs in access.db is probably
a good one for now.



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