PTR record checks for sender domain?

[Kogo]

I got a message from someone warning:

Someone needs to tell your system adminstrator that the IP address sending out your company's email does not have a DNS PTR record that points back to "makecor.com". Instead, it is pointing to the original PTR record from your ISP ("67.104.224.132.ptr.us.xo.net").

If this isn't taken care of soon, you're emails will be trapped by newer spam filters and email systems (including AOL).

This seems to me to be very unlikely... any chance it's true?

[MrByte]

Take a look at http://www.dnsreport.com/tools/dnsrepor ... akecor.com

Even tough there is a PTR record for mail.makecor.com, it seems to be a generic one from your provider?
Also, are you sending mail trough your ISP's SMTP server?

[Kogo]

Useful report - I requested the PTR record myself, but I administer the more common DNS settings myself.

This brings up an important question - my mail server is primarily mail.id-8.com, but I host several domains. Should each domain have an MX record poiting to my primary domain (like mx.id-8.com) OR should each one have an MX record pointing to its own domain (mx.domain1.com, mx.domain2.com) even though the IP target will be the same?

[Kogo]

Bump... any guidelines?

[MrByte]

each domain you host, should have an MX record pointing to mx.domainx.com and the A record for each, will point to the same IP address, i.e:
domain1
MX mx.domain1.com
A mx.domain1.com 67.104.224.132

domain2
MX mx.domain2.com
A mx.domain2.com 67.104.224.132

etc.

BUT, there will (and can be) only 1 PTR record for 67.104.224.132

[Kogo]

Thanks VERY MUCH! That's what I have and it's great to get the confirmation I needed.