[CentOS] sendmail mail relay backscatter issue.
simon at houxou.com
Thu Feb 4 15:09:53 UTC 2010
> > I would question how "real time" that would be for every email for
> > domains. If a few have a large client base, or are expecting
> > from a mass emailing, it might start to take a *while*, unless you've
> > pretty heavy duty equipment and networking.
> It's the same thing the downstream server is going to have to repeat in
> just a
> moment anyway, but this time it doesn't have to do the other steps. If
> you are
> close to capacity already it might push you over the edge - and be
> scripting a way to maintain that frontend virtuser table that makes it
> near-instant hash lookup for the relay sendmail. But for the relay it
> will be a
> win either way to avoid the much heavier load of spam-scanning stuff to
> recipients and making the downstream servers construct bounces.
I hadn't looked at it like that, you may be right, the reduction in scanning
may provide enough capacity to handle the additional workload from perl. I
think that I would prefer to have sendmail do the "rcpt to:" rejection
utilising a map as this I think will be the fastest method, so I'll check
out the virtusertable approach.
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