The Boston Diaries

The ongoing saga of a programmer who doesn't live in Boston, nor does he even like Boston, but yet named his weblog/journal “The Boston Diaries.”

Go figure.

Wednesday, August 23, 2000

Sendmail Blows, and here's why

My my my … it looks like sendmail might be the culprit here, not Exchange. As per RFC-821:

      "User name" is a fuzzy term and used purposely.  If a host
      implements the VRFY or EXPN commands then at least local mailboxes
      must be recognized as "user names".  If a host chooses to
      recognize other strings as "user names" that is allowed.

      In some hosts the distinction between a mailing list and an alias
      for a single mailbox is a bit fuzzy, since a common data structure
      may hold both types of entries, and it is possible to have mailing
      lists of one mailbox.  If a request is made to verify a mailing
      list a positive response can be given if on receipt of a message
      so addressed it will be delivered to everyone on the list,
      otherwise an error should be reported (e.g., "550 That is a
      mailing list, not a user").  If a request is made to expand a user
      name a positive response can be formed by returning a list
      containing one name, or an error can be reported (e.g., "550 That
      is a user name, not a mailing list").

RFC-821, § 3.3. VERIFYING AND EXPANDING


         EXPAND (EXPN)

            This command asks the receiver to confirm that the argument
            identifies a mailing list, and if so, to return the
            membership of that list.  The full name of the users (if
            known) and the fully specified mailboxes are returned in a
            multiline reply.

            This command has no effect on any of the reverse-path
            buffer, the forward-path buffer, or the mail data buffer.

RFC-821, § 4.1.1. COMMAND SEMANTICS

From my reading, it seems that sendmail should not be sending back the program name, but rather, it should just return the email address passed in.

This is not good …

Obligatory Picture

[It's the most wonderful time of the year!]

Obligatory Contact Info

Obligatory Feeds

Obligatory Links

Obligatory Miscellaneous

You have my permission to link freely to any entry here. Go ahead, I won't bite. I promise.

The dates are the permanent links to that day's entries (or entry, if there is only one entry). The titles are the permanent links to that entry only. The format for the links are simple: Start with the base link for this site: http://boston.conman.org/, then add the date you are interested in, say 2000/08/01, so that would make the final URL:

http://boston.conman.org/2000/08/01

You can also specify the entire month by leaving off the day portion. You can even select an arbitrary portion of time.

You may also note subtle shading of the links and that's intentional: the “closer” the link is (relative to the page) the “brighter” it appears. It's an experiment in using color shading to denote the distance a link is from here. If you don't notice it, don't worry; it's not all that important.

It is assumed that every brand name, slogan, corporate name, symbol, design element, et cetera mentioned in these pages is a protected and/or trademarked entity, the sole property of its owner(s), and acknowledgement of this status is implied.

Copyright © 1999-2021 by Sean Conner. All Rights Reserved.