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I have a email server (iRedmail on Ubuntu) where I host my personal domain, and several other domains. Despite the fact that non of the domains spam, somehow, MXtoolbox tells me my server is on the Spamhaus ZEN blacklist. This server is a VERY low traffic mailhost, the only domain that actually "sends" any quantity of email from the server is my personal domain, with me and my wife having our email accounts there. The remainder of the domains hosted are one small local startup non-profit that has one email address hosted for incoming email (currently ONLY incoming), another is a domain for a small business some friends and I are trying to start, and another is my ebay business. Anyway enough background.. I'm trying to tighten up the server, MXToolbox already shows its ok as to "open-relay".. But since everywhere I look, says doing an spf record on the dns host is a good thing, I'm trying to set one up. What I'm seriously UNclear about, is how I add the other domains that this server is supposed to send/receive mail for in the spf record (I'm trying to use the spf wizard at www.spfwizard.net).. Do I need an spf record on each domain referring to my personal domain (which is the domain the server "lives" in). I have successfully (according to the MXToolbox spf record checker) added a spf record to my personal domain as follows
frandin.org. IN TXT "v=spf1 mx a ip4:188.8.131.52/32 ?all"
I guess my main question is do I need an spf record in each domain?