Re: Postmaster 'best practices' query

["Brett Frankenberger" <rbf () rbfnet com>]

> IOW: Which of the following are required vice recommended vice
> best practives, etc.
>
> a)    postmaster () example com
> b)    postmaster () mail example com
> c)    postmaster () wizzbang example com
> d)    postmaster () pop example com
> e)    postmaster () cisco example com
>
> and most important to me: where to I go to justify the
> decisions on same?

2821 (section 4.5.1) says that "postmaster" (with no domain" must be
accepted as:
 (a) a local name (with no domain specified, as in: RCPT TO:<Postmaster>"
 (b) A mailbox at every domain for which the mail server accepts mail.

That means that the answer to your five questions are are:
 a) postmaster () example com is required if any mail addressed to
@example.com is accepted.
 b) postmaster () mail exam is required if any mail addressed to
@mail.example.com is accepted.
 c), d), e) follow the example above.

Had you also included: 
  f)   postmaster

The answer would be "yes, that is required".

RFC2821 would be a good place to go to justify decisions on same. 
(Well, to justify a decision to implement
postmaster () any domain for which mail is.accepted, and to implement
"postmaster".    It wouldn't really help you justify a decision to not
implement that.  OTOH, if someone is arguing that the the mere
existance of xyz.com implies that postmaster () xyz com must exist, then I
would note that neither RFC2821 nor any other RFC of which I am aware
imposes such a requirement.  As long as @xyz.com isn't being used for
any mail, there is no requirement for postmaster () xyz com to exist.)

     -- Brett