On 10/07/2007, at 7:42 PM, Simon Lyall wrote:
On Tue, 10 Jul 2007, Martin Kealey wrote:
What proportion of valid mail in NZ is sent from an address that doesn't have an MX record? Do you check? What do you do if it's not? If one were to block email from addresses without MX records, how much would break? How many complaints would one get?
You'd break a bit. Lots of automated emails come from addresses like "root(a)machine.domain.co.nz" which won't have a MX record or possible any (remotely viewable) DNS at all.
Unless you are going to block a huge amount of spam by doing it then it is probably not a good idea.
Yes, from what I can tell, iHug started doing this recently. Wait, no, they are checking that my mail server would accept messages for the envelope sender address. Because mail from a bunch of users' PHP code has an envelope sender of apache(a)hostname (but a valid "From:" header in each email), I have to accept mail for apache(a)hostname (or at least pretend I do). it's not really a /huge/ problem, but it's annoying to have to do so. Infact, I haven't bothered yet. -- Nathan Ward