Phillip Hutchings <[EMAIL PROTECTED]> writes: >> But this license-plate analogy only applies to the faulty MX record. >> According to the original poster, that site had _two_ MX records: >> >> MX 8 n.n.n.n. (faulty) >> MX 10 mail.foobar.com. (correct) >> >> Why couldn't Courier try the correct MX record after the faulty one >> fails? I don't know of any RFC's that would be violated in that case, >> and in fact, I thought that this is what an MTA is _supposed_ to do. > > Cars have two registration plates, one on the front, and one on the > back. The police stop you if either is missing. > > The point is the standard is the standard, and if nobody enforces it all > hell breaks loose. There's no particular reason for courier to be this > enforcer, other than the Sam Varshavchik, the author who kindly gives > away this software, has chosen to. You're quite welcome to use Postfix > or Sendmail if you like driving with your registration plates on the > roof and underware on your head.
If "a standard is a standard", then why are you suggesting that we refuse to implement one of the options specified in the standard specified in RFC 974? Here's the pertinent section: If the list of MX RRs is not empty, the mailer should try to deliver the message to the MXs in order (lowest preference value tried first). The mailer is required to attempt delivery to the lowest valued MX. Implementors are encouraged to write mailers so that they try the MXs in order until one of the MXs accepts the message, or all the MXs have been tried. A somewhat less demanding system, in which a fixed number of MXs is tried, is also reasonable. Note that multiple MXs may have the same preference value. In this case, all MXs at with a given value must be tried before any of a higher value are tried. In addition, in the special case in which there are several MXs with the lowest preference value, all of them should be tried before a message is deemed undeliverable. The "preference value" is the "8" or the "10" value in the the MX records mentioned above. The way that Courier functions now (i.e., using a fixed number of MX tries, where that number is 1) and the logic of trying multiple MX's are both correct according to this standard. RFC 1035 says nothing about this preference value, but it refers to RFC 935 for details of MX processing. > I still see no valid reason to put an ip address as an MX. Agreed. That logic is used for rejecting the faulty n.n.n.n. record, which I agree should be rejected. And RFC 974 says that it is perfectly consistent with standards to try the mail.foobar.com. record after the n.n.n.n. record has been properly rejected. I am starting to write a Courier patch which will cause it to use the logic specified in RFC 974. I will make it so that this is controlled by a BOFH variable, with the default being today's behavior. Assuming that I don't get hit with any extra work, I should be able to post that patch here within a week. -- Lloyd Zusman 01234567 <-- The world famous Indent-o-Meter [EMAIL PROTECTED] ^ God bless you. ------------------------------------------------------- This SF.Net email is sponsored by: Oracle 10g Get certified on the hottest thing ever to hit the market... Oracle 10g. Take an Oracle 10g class now, and we'll give you the exam FREE. http://ads.osdn.com/?ad_id=3149&alloc_id=8166&op=click _______________________________________________ courier-users mailing list [EMAIL PROTECTED] Unsubscribe: https://lists.sourceforge.net/lists/listinfo/courier-users
