gds@SRI-SPAM.ARPA (Greg Skinner) (10/16/85)
Sorry that I let that one get out by mistake. Anyway, this is a suggestion for anyone who is implementing a name service that runs in conjunction with SMTP, such as the pathalias uucp-path server on harvard. I propose that when handed foreign addresses, it queries the server *before* attempting the delivery. For example, I have handed to the SMTP server at harvard addresses of the form: VRFY houxm!gregbo and gotten a 250 <houxm!gregbo> response. When the attempt to actually deliver the mail is made, however, I have received lines of the form: bad system name: houxm uux failed: code 68 which leads me to believe that the name server is not operating. What I would like to see is some interaction with the name server before an OK response is made, so that in case a server is down, a message such as: 550 Requested action not taken: Name service unavailable or at least a 251 User not local; trying houxm!gregbo so when the RCPT TO: command is sent the name server will have already failed, and can return with the 550 command. This is not intended to be specific to Unix (although this problem may very well be) but generalizable to all name service (for example, bitnet may wish to provide a service at wiscvm). Comments are welcome. Criticisms of Unix are not, let's please keep to the subject. --gregbo