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

Phil Pennock wrote:
> On 2008-01-15 at 03:22 +0000, W B Hacker wrote:
>> Though I agree (from actual testing) that use of port 80 is a bad idea,
>> for smtp - the above does not apply in practice.
>
> It does when you want to provide _both_ SMTP and HTTP on the same IP on
> the same port, concurrently.

Yes, indeed.

>
> There are other sets of protocols where you can run a daemon service
> which supports more than one protocol and dispatches accordingly; the
> cases I know of all rely upon the client sending first. Where the
> server sends first, it theoretically would be possible, if you can come
> up with a greeting banner which is compliant to both protocols.
> Probably just about possible in some cases.
>

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.

And - given the plethora of better options that are known to work just
fine from airport lounges, hotels, coffee shops, fast-food outlets and
bookstores during my own globe-trotting, I cannot think of a good reason
- or need - to want to do it at all.

;-)


> None of which helps when SMTP sends the banner first and the client is
> supposed to wait for the banner first, whilst HTTP speaks first and
> there are then inherent race conditions. A multi-second timeout for
> waiting for an HTTP request would be possible but would be far too
> fragile for use in a production environment with paying customers.
>
> -Phil
>

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

Bill