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I have multiple domains with multiple mailservers on each. they all send with the same return path address. so for instance.

I want to authorize any host on my domains (,, and ) to send for

The domains listed above are mine and do not have spf records at this time.

I tried

v=spf1 a ~all

but that did not seem to work,because I may have multiple mailservers for etc.

Any ideas?

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You can allow each domain's MX in that particular domain's SPF record. Then for the '' domain, include the other domains

TXT  "v=spf1 mx -all"
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Wildcard SPF should in theory work ( but the reality is that it isn't totally reliable. It isn't too hard to setup the individual entries per domain in form of

v=spf1 a mx ~all

but some dns setups have a limit of the number of servers you have. It may be better to do it by IP address if the domains are hosted on the same box. Will give less maintenance.

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Try setting the wildcard record for IN TXT, eg:

* IN TXT "v=spf1 -all"
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you mean have this entry in each of my domains and then include it in the spf record? – Brian G Aug 28 '09 at 17:12
Sorry, I thought you meant you wants subdomains of those domains all authenticated. SPF works based on IP addresses; not domains - so you can authorize the list of IPs that will be sending mail for or the other domains. – Dave Drager Aug 28 '09 at 17:29
SPF does allow domain names. See for examples – Ryaner Aug 28 '09 at 20:04

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