Hi Roger,
On Sat, 26 Feb 2011, Jeremy Harris wrote:
> On 2011-02-26 09:57, Roger Burton West wrote:
>> I have two MX machines, call them mx0 and mx1; mx0 is the lower-priority
>> and does deliveries to users. As is the way of the world, mx1 gets hit
>> by a lot of spammers with scraped addresses which will be undeliverable
>> (e.g. message-IDs). At the moment, mx1 accepts the message (assuming it
>> passes the spam filter), and forwards it to mx0, which rejects it; then
>> mx1 tries to send a bounce message to the (faked) originator.
>
> Option 1) have both systems lookup the same database (or copies thereof)
> in deciding whether an address is valid
>
> Option 2) have the slave system do a recipient-verify callout to the master
> system
Option 3) have the secondary only accept mail when the primary is down
(possibly combined with 2):
http://blog.aptivate.org/2009/01/28/backup-mail-exchangers/
Cheers, Chris.
--
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\ __/ / ,__(_)_ | Chris Wilson <chris+sig@???> Cambs UK |
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