Re: genuine bulk email

Jeffrey Goldberg wrote:
On Oct 12, 2007, at 9:40 AM, Robin Becker wrote:

these all sound very reasonable. However, we use the same IP for several virtual hosts ie we have more than one domain name so the reverse DNS is not clear to me. Is the from address inspected for comparison with the RDNS ie if I claim to be sending from xxx.com should my RDNS point back to xxx.com? Presumably I can have only one IP-->domain ptr. I suspect it will be easier to set up the front end machine as that is supposed to be for the same client.

The checking will work fine with virtual domains. What matters is that

DNS(rDNS(IP)) = IP = DNS(vhost)

I think I've got that right. (It's a bit more complicated to state when MXes and multiple A records for the same name are considered, but this is the general idea.)

Also it's not so much the header FROM or the envelope FROM, but the HELO string that is checked here. For SPF and DomainKeys, it is the envelope FROM that is checked against the IP. Presumably your mailer gives a constant HELO irrespective of the vhost that is in the envelope FROM.


OK this makes better sense. So long as my internal machine name matches the equation above then I should be OK no matter what. I'm fairly sure I've got stuff set up properly. I do need to set up the appropriate rDNS and check the HELO on the test machine though. The HELO looks right, but my rDNS is shot and I am currently in the CBL for some reason.


And how do the sales people acquire the data? I'm sure that it's okay, but you may want to have a small description of the process on your web page that you could point postmasters to if a question arises.
......
these are telephone sales people so far as I know. When they're booking the room(s) for the client they ask if they want to receive an emailed document describing the hotel etc etc so it's not bulk in the sense of database --> email and certainly we're not recording any of the details at all. I suppose we could be used by our client as a spurious mail sender, but it would not be terribly fast and it's unlikely as they likely could do it much easier themselves.
--
Robin Becker
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