Re: [exim] ACL to drop connectio

On Fri, 2010-06-11 at 13:09 -0400, W B Hacker wrote:
> That's quite elegant! (Given one understands '0' means 'infinity' here)

Thanks. For "Understanding" replace with "the documentation for this
option states that" :)

> But is it 'cheap'?

Not as "cheap" as not doing the lookup, obviously. And if you had a
bazillion hosts/netblocks in your hostlist it would probably be quite
slow; but if you had that, you'd be doing it wrong.

The fact that it acts before any SMTP processing is done makes it pretty
lightweight. Given that recipient verification further down the
transaction will cost many times more resources, deferring connections
before you've even sent a banner is worth a lot.

So yes - it's "cheap".

Graeme