I suppose it depends on definition of "trustworthy". I had the experience with SendGrid, of them adding new servers without rDNS information. I called in and astoundingly enough, their "technical" person explained to me DNS didn't matter, and he had no interest in addressing it.
A trustworthy operation, always takes care of the plumbing. ________________________________ From: David Jones <djo...@ena.com> Sent: Sunday, October 9, 2016 1:03:42 PM To: Alex; SA Mailing list Subject: Re: whitelist_auth and how to test >The sender is sendgrid.net, using an Envelope-From that contains a >random ID, making it impossible to use the whole address for the >whitelist_auth entry. >It's probably not a good idea to penalize sendgrid.net with 1.5 >points, but I'm more interested in how to properly whitelist mails >like this for now. >Perhaps there's a better way to deal with bulk mailers like sendgrid >you might recommend? Sendgrid.net is trustworthy and has a valid unsubscribe process so they should be whitelisted safely with whitelist_auth. Let your users decide for themselves if they want to unsubscribe from any email sent by sendgrid.net. whitelist_auth *@sendgrid.net There are many safe bulk senders like this. It comes down to good reputation with a valid opt-out process.
