Re: [Exim] Server response to error codes

On Mon, 28 Jun 2004 00:12:23 -0400 (EDT)
"Greg A. Woods" <woods@???> wrote:

> [ On Saturday, June 26, 2004 at 16:29:25 (-0500), Craig Jackson wrote: ]
> > Subject: [Exim] Server response to error codes
> >
> > Does anyone have a source of information on various mail servers and
> > their response to error codes?
> >
> > Recently I implemented greylisting on my server named Mailscan (Exim
> > 4.34); but I noticed that our Groupwise 5.5 bounces the outgoing mail to
> > the greylisting Exim server at 451 after RCPT. This is a test situation
> > now.
>
> "bounce" and "451" does not compute. :-)
>
> As we all know any 4xx response code is a _temporary_ error.
>
> Do you mean the GroupWise server returned a 451 response to the RCPT
> command sent by Exim? Or do you mean the GroupWise server treated a 451
> response to its own RCPT command as a permanent error and did not retry
> delivery of the message as it should?
>
> I'm guessing you mean the latter, given the context.
>
> Have you checked to see if there are any configuration options on the
> GroupWise server that might change its behaviour?
>
> > I need to know what other mail servers are going to do with a 451.
> >
> > Any information sources on this?
>
> I've never run across any such list that even begins to cover just the
> most common servers.
>
> A counter question might be: Do you have any idea what types of mail
> servers make up the majority of those originating the normal legitimate
> traffic your site receives?
>
> I.e. since you don't care what any sources of unwanted traffic do with
> any temporary error code you might send them (that's the whole point of
> implementing something like greylisting after all, isn't it?) so if you
> narrow your question down to just those specific types of mailers that
> you know you get the majority of your legitimate traffic from then you
> can begin to target your question to those who are more likely to be
> able to answer it. :-)
>
> --

Greg,

I've never bothered with the Groupwise server, never had cause to. But looks like it's time to do some fixin', so right, the latter is correct.

I realize it was sort of a hair-brained question, but we get mail from probably every type of server known, but mostly exchange. Yours is a good suggestion, though. I'll compile a list of sending servers, esp the important mail. My fear in implememnting something like greylisting is that if I get a bounce the FIRST time I test it from another server, then it is 100% guaranteed that one of the top people in the firm will have a similar problem several times within the first 2 months and will probably be pissed -- at me. We'll see. Because on my test server, ZERO spam is getting through so far, and only one false bounce positive.

Thanks,
Craig