SPF Configurations

Bret Clark bclark at spectraaccess.com
Fri Dec 4 10:48:21 CST 2009

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.


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 at billtrust.com
> -----Original Message-----
> From: Joe St Sauver [mailto:joe at 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

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