darkage - 9:24 pm on Jan 10, 2012 (gmt 0)
Allow me to provide an example:
VPS is hosting example1.com and example2.com
Both sites uses sendmail to send out bulk newsletters.
sendmail is configured to represent example1.com properly, so no emails sent from example1.com will be rejected by the receiver.
if example2.com uses sendmail, the receiver might reject it due to PTR, header checks, etc.
What's the best way to address this ?