Wednesday, December 8, 2010

Reverse DNS, a Domino/Traveler Box and Comcast

This post is dedicated to Comcast who never tells Business class customers what is changing in their infrastructure or admits anything changed.

Come in on Monday and started receiving unable to send emails like 554 error.

Knowing we didn't change anything on our end or the client's end yet comcast was an error on a message, so I called them.

They said the problem is on our side. I said but nothing has changed on our side.
Sorry we can't help you was the reply.

So for the sake of argument, a bunch of companies, who we have no relationship to aside from an email one about information, miraculously all changed their spam appliances or security methods at the same time.

Not too likely.

So I tested our domains, this was affecting Traveler and regular Domino email, for reverse dns entries.

All our sites were now showing comcast as the reverse entry, no longer the appropriate sites.

Logged in to the registrar of the domains and decided to add a new A record for mail to the domain. Maila I called it.

Saved, rechecked and now the domain was found correctly.

What is going on? Still no idea, Comcast isn't saying but we changed every single domain that works with Comcast, just in case, to ensure phones were not getting filled with undeliverable mail notices.

So if you use Comcast, check your reverse dns records.