Finally set up a proper SPF record this evening for my domain, hopefully that’ll help at least a little in the fight against spammers.

I tried it before, but I think I hit difficulties getting the right format for TinyDNS zonefiles, and put it off.

For future reference, the format I used was:


'preshweb.co.uk:v=spf1 ip4\07280.68.91.76 ip4\07280.68.82.38 ip4\07280.68.81.0/24 a\072supernova.preshweb.co.uk -all


Now I just need to set up null SPF records on a few domains I hold that I don’t send mail from, to indicate that no mail should ever originate from those domains.

Next step will be to configure my incoming mail server to do SPF authentication and reject mail for which it gets an SPF fail.

There’s plenty of useful info about SPF over at openspf.org.