On 03/06/2019 09:37, Sam Hartman wrote: > I'd much rather pay money and allow members who do want to use their own > infrastructure to do so rather than set up an SPF record and force > everyone to go through the debian mxes. Pay money for which service exactly? I am not aware of any widely deployed whitelist that filters on source address, which I think would be the only solution that would allow members to use their own infrastructure. Cheers, Dan