If the customer insist on using their domain, then you would have to have the customer setup an SPF record within their domain that points to your email server IP blocks. I would just tell your customer that if they insist of using their FROM domain, to help get past someone's spamming system the customer is going to have to add the a SPF record to their domain similar to the following: [customer domain].com. IN TXT "v=spf1 a mx ip4:[your IP block] Putting an SPF record in your DNS record will have no affect on spamming software. SPF is basically another form of reverse DNS at the mail level. Bret Jeffrey Negro wrote:
Thanks for your input on this. My main concern is mail filters at the end users side thinking that our mail servers are spoofing our customer's domain. I'll check into MAAWG as well
Jeffrey Negro, Network Engineer Billtrust - Improving Your Billing, Improving Your Business www.billtrust.com 609.235.1010 x137 jnegro@billtrust.com
-----Original Message----- From: Joe St Sauver [mailto:joe@oregon.uoregon.edu] Sent: Friday, December 04, 2009 11:25 AM To: Jeffrey Negro Subject: Re: SPF Configurations
#Some customers insist on #making the FROM address use their domain name, but the emails leave our #mail servers on our domain.
Then your IPs or outbound mail servers should be listed on the customer's SPF record... assuming they also send their own mail, they obviously also want to list their own mail servers.
#SPF seems to be the way we could possibly avoid more spam filters,
SPF only provides a way of avoiding spoofing, it does not necessarily enhance your IP reputation or your domain reputation
#and delivery rate is very important to our company.
Are you involved with MAAWG? (see www.maawg.org)
Regards,
Joe