Ben, Thanks for running your questions by me. Feel free to forward this message to your Comcast rep. Even if he is unwilling to help you further, there is information below that will help him be more accurate in future cases, since he currently lacks sufficient understanding of DNS.
Mr. Jones is seemingly unaware of the difference between a delegated subdomain and a hostname. This gap in understanding does call the other conclusions into question, and I would not consider his to be an expert-level response. NOTE: I don't know if Comcast is or is not ultimately at fault for your mail delivery problems, but I would advise you to look for more expert testimony. It's perfectly normal for a hostname to be both the label and the value of an MX record (i.e. to "be its own MX"). In fact, the RFC-specified behavior of SMTP is to connect to the hostname to deliver mail to user@hostname in the absence of an MX record. All you are doing by adding <hostname> IN MX <hostname> is specifying that which would already be assumed (and also taking advantage of the MX algorithm). So normal is this configuration that I was able to quickly dig these examples from large, reputable domains: mail.beta.army.mil IN MX 10 mail.beta.army.mil ajax1.rutgers.edu IN MX 10 ajax1.rutgers.edu web.mail.vt.edu IN MX 0 web.mail.vt.edu webmail.uic.edu IN MX 0 webmail.uic.edu mail.messaging.microsoft.com IN MX 10 mail.messaging.microsoft.com webmail.villanova.edu IN MX 0 webmail.villanova.edu smtp01in.umuc.edu IN MX 0 smtp01in.umuc.edu mta4.wiscmail.wisc.edu IN MX 0 mta4.wiscmail.wisc.edu mail.dotster.com IN MX 0 mail.dotster.com Good luck with your continued troubleshooting! -- Sandy --- This E-mail came from the Declude.JunkMail mailing list. To unsubscribe, just send an E-mail to imail...@declude.com, and type "unsubscribe Declude.JunkMail". The archives can be found at http://www.mail-archive.com.
