From: Victor Duchovni on
On Thu, Jun 03, 2010 at 08:32:16PM +0200, Moe wrote:

> Remember we're talking about the case of auto-detection here
> - if someone is not willing to take that risk then they should hardcode
> 'myhostname' and 'mydomainname' in main.cf, no?
>
> Moreover I'd suggest that postfix may very well accept a FQDN from
> gethostname() if that returns a value that contains dots. That way
> people who prefer it that way can have theirs, and people who take
> 'gethostname()' literally get theirs, too.

You don't understand Postfix well enough. Determining the system name is
not a cosmetic nicety for an MTA. The system name has important consequences
for delivery and addressing of local mail. How Postfix does this has been
thought out with care.

In fact it is a feature that Debian laptops appear to be
"shortname.localdomain" rather than an FQDN in some random ISP's domain.

We should close this thread. Over and out.

--
Viktor.

From: Wietse Venema on
If you want Postfix to use a some value other than the default
("localdomain" or the kernel domain name), then you must update
the appropriate Postfix configuration parameter.

If you object to the idea of having to update a Postfix configuration
parameter, then you must not use Postfix.

Wietse

From: Victor Duchovni on
On Thu, Jun 03, 2010 at 08:36:52PM +0200, Moe wrote:

> My point is: When 'myhostname' and 'mydomainname' are left out of
> main.cf then postfix makes an attempt to auto-detect them.

These are MTA configuration variables.

> This auto-detection does not currently follow what other tools like
> 'hostname' do, and not what the man-pages of gethostname()/uname(),
> getdomainname() suggest.

The man-pages in question have nothing to do with Postfix configuration
variables.

The correct way to not duplicate the MTA name into main.cf, while
getting the desired domain appended to the host's short-name, if
the default "localdomain" is not appropriate is to add:

mydomain = example.com

to the top of main.cf.

> You suggest this auto-detection is deliberately done wrong to protect
> users on misconfigured hosts from themselves.

It is deliberately done right to ensure reliability, stability and
correct operation of non-networked hosts. Please stop. And close the
Debian bug-report please, if you persist too much, someone who understands
Postfix poorly may decide to fix the "bug" for the Debian community.

Yes, this would not be quite as dramatic as the OpenSSL PRNG botch, but
it would still be a mistake, and cause needless pain and effort to undo.

--
Viktor.

From: Jim Wright on
On Jun 3, 2010, at 1:36 PM, Moe wrote:

> My point is: When 'myhostname' and 'mydomainname' are left out of main.cf then postfix makes an attempt to auto-detect them.

There's your problem. Fix that. See my original reply at the start of this thread.
From: "N. Yaakov Ziskind" on
Jim Wright wrote (on Thu, Jun 03, 2010 at 04:47:05PM -0500):
> On Jun 3, 2010, at 1:36 PM, Moe wrote:
>
> > My point is: When 'myhostname' and 'mydomainname' are left out of main.cf then postfix makes an attempt to auto-detect them.
>
> There's your problem. Fix that. See my original reply at the start of this thread.

More than that: Debian *does* fix that. See the second message in the
original link: you have to *remove* something that Debian puts in,
otherwise you never experience the bug.

So, the whole thing seems kinda metaphysical.