[CentOS] question for those who run mail servers

[m.roth at 5-cent.us]

Bob Hoffman wrote:
> Not technically a centos question, but a lot of you guys seem to manage
> some large systems and I could use some clarification on a postfix
setting.*
>
> *reject_unknown_client_hostname
> (in postfix < 2.3 reject_unknown_client)
>
> When I first used this there were issues with users trying to send mail
> through the server from hotels, wireless spots, etc. This was solved by
pushing up permit
> sasl_authenticated.

This caught my eye: they don't have an account on those hotspots, they
*have* to be connecting, via mailtool or webmail, to their *real*
mailserver, I would think.
>
<snip>
> not see how this could be a bad setting and am thinking of using it.
> A person sending out a mail to the server, even if in that badly set up
> hotel wireless should be using their gmail, yahoo, own server, isp mail
servers and
> should not be directly sending from their iphone....is that correct?

I guarantee that those folks with too-"smart"-for-their-own-good phones
will send directly from them. Having never looked at a header from an
email sent via iPhone, I don't know - don't they have a legit mailserver
as their gateway?
<snip>
       mark