[Greylist-users] What timeouts should be used with greylisting
David F. Skoll
dfs at roaringpenguin.com
Wed Jun 25 14:16:01 PDT 2003
On Wed, 25 Jun 2003, DJ Delorie wrote:
> What I do is add a 60 second delay before sending them the error code.
That's fine on a small mail server. It's horrendous on a busy mail
server. You'd see sendmail (or exim or qmail or whatever) processes
backing up like crazy, chewing up your virtual memory.
Believe me, I know that adding delays to responses on a busy server
> It's not the bandwidth that's important, it's the number of emails per
> hour they send that is.
Multi-threaded spam engines on commodity hardware can easily run
thousands of parallel SMTP sessions simultaneously and probably
saturate a 100Mb/s Ethernet. Adding delays on your end will have an
infinitessimal effect on hard-core spamware.
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