I have a domain who's users send email from an isp's smtp server. I'm trying to set up SPF for that domain using:
v=spf1 a mx include:mail.isp.com ~all
When I checked the record using The 2nd tool at http://www.kitterman.com/spf/validate.html it gave me an error becuase the isp doesn't have SPF records for their domain.
My main question - Does this mean I should just not use SPF? Will this cause problems leaving in the record for their normal email use? I have a list I need to send out so I'm trying to be as proactive as possible to make sure it delivers well.
Also, a side issue is my SPF record does not show up via the 1st tool at http://www.kitterman.com/spf/validate.html even thogh I'm fairly certain DNS has propagated. I'm giving it another day before I worry about that too much but wanted to mention it in case it's related.
Edit: Ok, I figured out that while mail.isp.com has no SPF records, isp.com does. Here it is(with a hypothetical ip address):
v=spf1 ip4:18.104.22.168/24 ?all
What confuses me is that the ip address of mail.isp.com is included in that ip range. I guess I can do the same thing with an ip range and see how that works out, and count the range as neutral with ? or something. But why isn't specifying the domain working in this case?