Wiebe Cazemier:
> That's why I was asking if it wouldn't be a good idea to have
> 'permit' be a viable option for unverified_recipient_tempfail_action.
unverified_recipient_tempfail_action is triggered when:
- The backup MX could not reach the primary MX.
- The primary MX replied with a 4xx response.
In both cases, the backup MX will not know if the recipient
address is valid.
> That way, you will not create spam-induced backscatter 99% of the
> time and still function as a proper backup MX.
No, in both cases, the backup MX will not know if the recipient
address is valid. Therefore, accepting the email can result in
backscatter.
Your 99% number contradicts current measurements that indicate that
most mail is spam.
Wietse
