Re: domain names, was: hostname

[Brian <ad44@cityscape.co.uk>]

On Fri 23 Mar 2018 at 10:46:22 -0500, David Wright wrote:

> On Fri 23 Mar 2018 at 10:31:13 (-0000), Dan Purgert wrote:
> > 
> > This is where things get messy, due to language.  In the context that
> > Greg is using, "receiver" is the ultimate destination MTA, and not the
> > intermediary MTA(s) that a message may be handled by.
> 
> In that case, this is the step of least concern to the ".home user"

Indeed. For the user it's fire and forget. Once the mail is handed over
to the smarthost it would be the entity assuming responsibility for the
delivery of the mail. That's really the whole part of of its existence.

> as it's the most distant. What's of concern to this user who's trying
> to determine whether give their LAN a domain name is mail *submission*,
> because that's where the difference between a FQDN of foo and foo.home
> might affect their smarthost's willingness to perform its role.

There are some ISPs who would require the EHLO/HELO to have a dot in it,
so then /etc/hosts would have to be suitable. However, I suspect the
majority of (large) ISPs (for example, cox.net, bt.com, talktalk.co.uk
and, as we have seen, unlimitedwebhosting.co.uk) accept more or less any
old rubbish for the EHLO/HELO. On the whole, a Debian user can leave the
domain name in d-i empty (or make something up).

Imagine support at verizon.net having to explain to a user that the HELO
her Windows OS mailer was sending wasn't quite up to scratch. :)

-- 
Brian.