IMHO, yes. You should not have a PTR mismatch. This is a very basic anti-spam check.
-- Espi On Wed, Feb 7, 2018 at 1:45 PM, Mayo, Bill <bill.m...@pittcountync.gov> wrote: > My attempts at postmas...@earthlink.net and trou...@earthlink.net did not > work, so I tried the Twitter route. It took a while, but I did ultimately > get a response today where they gave me a phone number to call. So, thanks > to Michael and everyone else that responded. That said, based on the > conversation that I had, I would appreciate a reality check. > > > > We have 2 different ISPs and load balance outbound SMTP connections, as > well as inbound DNS queries. So, we basically have 2 different IP’s that > are used at the edge. We have an MX record that points to the domain name. > DNS lookups to that domain name will return one of the 2 IP’s. Both of > those IP’s will reverse lookup to the domain name. The HELO/EHLO greeting > from the server gives the same domain name as the MX record. Additionally, > we have an SPF record that indicates both of those IP’s. What Earthlink > seems to be initially suggesting is that they are doing an A record lookup > of the domain name and comparing that to the connecting IP address (which > seems contrary to the error message). In our setup, this will not always be > a match. I can understand that they would do a reverse DNS on the IP to > make sure it matches the HELO/EHLO greeting, and I can understand that they > might also do an SPF and/or MX lookup to make sure that matches. I don’t > understand doing a forward lookup and comparing that to the IP, since I > don’t think that having multiple A records for a given domain name is > particularly uncommon. Is what they are suggesting a legitimate issue? > > > > Bill Mayo > > > > *From:* listsad...@lists.myitforum.com [mailto:listsadmin@lists. > myitforum.com] *On Behalf Of *Michael B. Smith > *Sent:* Friday, February 02, 2018 10:49 AM > *To:* exchange@lists.myitforum.com > *Subject:* [Exchange] RE: Earthlink Contact? > > > > Twitter shame them. @Earthlink and @weCareEarthlink > > > > And yes, I’m completely serious. > > > > *From:* listsad...@lists.myitforum.com [mailto:listsadmin@lists. > myitforum.com <listsad...@lists.myitforum.com>] *On Behalf Of *Mayo, Bill > *Sent:* Friday, February 2, 2018 10:16 AM > *To:* exchange@lists.myitforum.com > *Subject:* [Exchange] Earthlink Contact? > > > > We are having emails sent to Earthlink being intermittently rejected with > the reason “550 ERROR: No or mismatched reverse DNS (PTR) entries”. We have > done quite a bit of troubleshooting on this, and the problem does not > appear to be on our end. I actually have logs that show 2 consecutive > messages where the first one is accepted and the second one rejected. I > also see “421 Load too high” messages in the log from Earthlink when these > happen. > > > I am trying to figure out how to contact Earthlink to get some assistance, > but am striking out with how to contact them. The have a special page if > you are getting a “blocked by EarthLink” response, but that doesn’t apply > here. There contact page has chat support that requires you to provide an > Earthlink account. Does anybody know how to get in touch with someone at > Earthlink that could actually help with this problem? > > > > Bill Mayo >
