--On Sunday, October 30, 2011 05:25 -0400 Hector Santos
<hsantos(_at_)santronics(_dot_)com> wrote:
...
220 SMTPRETRY
AUTH <stuff>
220 OK (which may need to be faked if the real auth database
is not available)
EHLO me again
220 SMTPRETRY
NEEDRETRYDATA
621 Server in maintenance, try later wait:600
We know you meant 250 above. Two comments.
On not, depending on what advertising the "NEEDRETRY" extension
means. It could open up the 6yz set of codes.
If the intent is know to issue a maintenance notice, then I
would probably not activate AUTH. So it becomes:
<connection>
S: 220 hi
C: EHLO me
S: 250 SMTPRETRY
...
Independent of the details, switching the set of extensions
offered when the server was effectively unavailable for a while
in the EHLO response is an option that hadn't occurred to me
that that I think makes a lot of sense.
Also, if this is one of the purposes, then maybe a service
keyword, like perhaps ALERT can work do this:
S: 220 hi
C: EHLO me
S: 250 ALERT OIL CHANGE. QUIT NOW and WAIT:600
C: QUIT
S: 221 see ya!
Some review of the requirements for arguments to EHLO reply
keywords is in order here, but the principle is an interesting
one. Like all other good extensions, if the client doesn't
recognize the keyword, it can ignore it. If it doesn't it knows
what the arguments mean.
...
Folks, I'm seeing lots and lots of messages and design options
here: Server announcements with more or less detail, overloading
old reply codes versus using new ones, whether or not a client
request (or acknowledgment) is needed, appropriateness of
connection-time announcements, per-session versus per-message
behaviors, and so on. My sense is that both the proposals that
have been written up have improved and that others have started
to emerge. In the process, the questions about whether or not
one or more features of this class would really be adopted and
useful get lost -- it is lots easier and more interesting to
focus on the design details.
May I suggest that it is time that those who think this is
worthwhile get together, off this list, and see if you can shape
one or more complete and coherent proposals, with analyses of
the tradeoffs as appropriate, and then come back here or to the
ADs?
john