The A record for outbound.eastex.net yields an IP that's different from the second PTR record that references that same FQDN. So A > PTR > A mapping is broken.
Plus, I seem to recall RFCs recommend not to have more than one PTR record for the same IP. RFC 1912 and maybe RFC 2181 if I'm remembering correctly. Hope that helps, Mark -- _________________________________________________________________ L. Mark Stone, Founder North America's Leading Zimbra VAR/BSP/Training Partner For Companies With Mission-Critical Email Needs ----- Original Message ----- | From: "Bill Cole via mailop" <[email protected]> | To: "Mike McTee via mailop" <[email protected]> | Sent: Thursday, August 1, 2024 4:40:01 PM | Subject: Re: [mailop] [E] Anyone from sbcglobal.net | On 2024-08-01 at 16:26:46 UTC-0400 (Thu, 1 Aug 2024 15:26:46 -0500) | Mike McTee via mailop <[email protected]> | is rumored to have said: || Their server bounces his messages with this error: || 550 5.7.1 Connections not accepted from servers without a valid sender || domain.flph840 Fix reverse DNS for 66.171.0.45 || But I sent a test message to his intended recipient and my test message was || received. || Our DNS has been "as is" for a very long time and we're not getting any rDNS || errors from any others. | They may be having a problem with the existence of 2 PTR records. It's not | formally wrong, but it's a good way to generate odd problems with people who | try to validate your DNS. || On 8/1/24 2:31 PM, Marcel Becker via mailop wrote: ||| On Thu, Aug 1, 2024 at 12:02 PM Mike McTee via mailop <[email protected]> wrote: ||| We're getting an odd response for one of our customers when they ||| try to email someone @sbcglobal.net < [ http://sbcglobal.net/ | ||| http://sbcglobal.net ] >. ||| Please email me directly if you have insight to that domain and ||| can assist. ||| That's AT&T. And what is the "odd response"? ||| _______________________________________________ ||| mailop mailing list ||| [email protected] ||| [ https://list.mailop.org/listinfo/mailop | ||| https://list.mailop.org/listinfo/mailop ] || _______________________________________________ || mailop mailing list || [email protected] || [ https://list.mailop.org/listinfo/mailop | || https://list.mailop.org/listinfo/mailop ] | [email protected] or [email protected] | (AKA @[email protected] and many *@billmail.scconsult.com addresses) | Not Currently Available For Hire | _______________________________________________ | mailop mailing list | [email protected] | https://list.mailop.org/listinfo/mailop _______________________________________________ mailop mailing list [email protected] https://list.mailop.org/listinfo/mailop
