How can I set up reverse DNS on my Ruby on Rails website?

Question

Thanks in advance for any help you can provide with this issue!

For my website, users are supposed to receive an activation email after registering. Some emails are not being received, and they're not going to spam filter folders, either.

After reviewing my integral_mailer log, I think I've uncovered the problem. Systems seem to be rejecting the messages because there is no reverse DNS information.

• Here is what Comcast had to say in reply to a rejected message: http://postmaster.comcast.net/smtp-error-codes.php#554)
• Here is what AOL had to say: http://postmaster.aol.com/Postmaster.Errors.php#421dnsnr
• I checked this article but couldn't set up my own reverse DNS: Setting up Reverse DNS Records

I'm somewhat of a novice with RoR. Can you guide me in setting up the required reverse DNS information for my mailer?

As background, here are details from user_mailer.rb:

class UserMailer < ActionMailer::Base
def signup_notification(user)
setup_email(user)
@subject    += 'Please activate your new account'
@body[:url]  = "http://website.com/activate/#{user.activation_code}"
end

From integral_mailer.rb:

module IntegralMailer
def perform_delivery_integral_mailer(mail)
destinations = mail.destinations
mail.ready_to_send

helo = smtp_settings[:helo] || "localhost.localdomain"

ActionMailer::Base::INTEGRAL_MAILER_SERVER.send_mail(helo, mail.from, destinations, mail.encoded)
end
end

Answer 1

The website is hosted on Joyent, though the domain is through Go Daddy. Go Daddy does not do reverse DNS (even if the website is hosted through it.) The solution was to contact Joyent and to request that it set up the reverse DNS.

http://wiki.joyent.com/wiki/display/gen/DNS+Guide explains how to set up the reverse DNS through Joyent.

After a day or two, AOL, Comcast, and others started accepting emails from the website.