[BlueOnyx:25394] Re: another 5210R item

[Larry Smith]

Michael,

  Understand your reasons.  I do not do shared hosting
(multiple hosts on one IP) so don't have that problem.
Run my own DNS so don't have that problem either
and do not do any DNS on hosting machines (have dedicated
DNS servers).

Only problem I have is the servers that check smtp
name against the called IP, and the modifications
I mentioned fix that for me.  Others host their way,
I will continue to do mine.

 Thanks for the answer.

PS:  How does this name issue work with certs and SNI?

-- 
Larry Smith
lesmith at ecsis.net

On Tue April 26 2022 18:33, Michael Stauber wrote:
> Hi Larry,
>
> >    Sendmail uses the "name" of  the interface as
> > its answer to a connection and with this entry
> > every IP answers as the server name instead of
> > the name given to that IP in DNS - which is incorrect.
> >
> > <quote sendmail.mc from 5210R)
> > define(`confSMTP_LOGIN_MSG',$?{if_name}${if_name}$|$j$. Sendmail Ready;
> > $b)dnl </quote>
> >
> > And this sendmail entry has been there since the
> > Cobalt days (comment right before it is mine,
> > I am "les").
> >
> > Have no idea why you would intentionally do that
> > but it creates incorrect output and issues (at least
> > to me and the sites we host).  Changed all of this
> > and reported it on the 5209R for the same reasons.
>
> What Sendmail or Postfix report back as MTA hostname is not really of
> any consequence or relevance. And in cases where all Vsites are on the
> same IP or an IP is used by multiple Vsites, it is less and less
> consequential that in all cases it reports back the hostname of the
> server itself. In fact it is even more desirable, as you don't want the
> SMTP banner read customer-A.com when customer-B.com connects, who has
> the 2nd, 3rd or 55th Vsite on the same IP.
>
> On the other hand the entries in /etc/hosts supersede any incorrect or
> missing DNS information for Vsites that you host. So you can in fact
> already send (local) email to users on freshly created Vsites that don't
> yet have their DNS or still have propagation issues. Likewise you can
> (locally) test Vsites w/o DNS and stuff like that, which is a lot more
> useful.
>
> That's why we have these entries in /etc/hosts. /shrug