Re: [Exim] Preventing exim from querying dns for localhost

On Sat, Nov 10, 2001 at 16:21, Philip Hazel wrote:
> I have had a thought. If you do NOT set primary_hostname, Exim will call
> the uname() function to find the name. If it then finds a name that is
> not fully qualified (that is, if there is no '.' in the name), Exim will
> call gethostbyname() in order to find the fully qualified name. (This is
> all documented under 'primary_hostname'). The gethostbyname() may be
> what is doing the DNS lookup. When you set primary_hostname explicitly,
> it won't do this.
Yes, I have thought of that as well and used a little program to check
this, but it works there (see attached code): MyMachine/localhost gets
resolved correctly without dialing in.

> Exim really expects to operate with a fully qualified host name, because
> hosts on the Internet are supposed to have such names.
That is another thing I had trouble with in Debian unstable/sid: exim
puts in the envelope-from-field the local address of the sender instead
of using the From: message header. As a result all messages get lost
without notification on several sites as they get rejected and no
suitable returnpath is there to bounce to. However, in woody/testing
everything works fine. What is strange as they seem to be the same
packages. Maybe a problem with a called application?

> > This could as well be an issue of libc6 resolver. Can an exim developer
> > comment on this perhaps?
>
> I'm afraid I'm the only Exim developer, so you'll have to make do with
> my comments...
Oh! I did not know that you are a developer and the one and only one.
I have looked for some meta project information, but have not found any.
You have done a great job with exim!

So, back to my RFC: issue of libc6 resolver?

... I have tested 3.33 (ssl version) and no change.

Bye, Steffen