Re: genuine bulk email

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.

Automatic mailing is fine. What is important is how the email addresses were acquired.
......

this isn't automatic, the sales people manually enter all the details.

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.

-j


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