Re: [exim] How to have port 80 open, along with a website?

On 2008-01-15 at 04:49 +0000, W B Hacker wrote:
> To one extent it *seems* as simple as adding to the list of advertised
> services (and handling the choice correctly). But re-inventing all
> common browsers is certainly not on even if MUA's would play correctly
> with it.

I'm thinking of cases where no client changes are needed. With
client-first, it's trivial to have the same code handle finger and http,
for instance. With judicious selection of protocols all based on the
same common framework, you can have multiple protocols supported on one
port.

220 fred.example.org ftpd speaking ESMTP is here

I would expect any FTP or SMTP client to be happy to receive such a
banner and to continue onwards; the server could then make a decision.

> ACK - http response delays are generally more 'in your face' than
> IMAP/POP/smtp at that point...

No; once the server has received an HTTP request from the client, it can
respond immediately. There's a delay for SMTP but not particularly more
than many SMTP servers already impose anyway, to catch clients which
don't speak SMTP in-sequence.

But it's fragile and would cause support nightmares, especially since
the users who'd have problems would be on the laggy dire networks where
every action has a multi-second delay and so they'd already be
irritable, if not outright angry, by the time that they phoned to
complain about the broken service. Combining HTTP and SMTP is not an
approach I would recommend at all, for the _technical_ reasons I noted.

I was wanting the OP to understand why it's in hard reality a bad route
to go, rather than just seeing a bunch of people telling him how to run
his business and expounding upon The Right Way, when he's already stated
an explicit constraint of only port 80 outbound being available.

I happen to agree with those people, but that didn't help the OP and
didn't show that we were trying to be helpful, not bossy.

-Phil