Re: notion of a local address [was: Re: ioctl SIOCGIFNETMASK: ip alias

[Wietse Venema]

Andrey Savochkin:
> Of course, SIOCGIFCONF isn't even close to provide the list of local
> addresses.
> Obvious example: it doesn't enlist all addresses 127.0.0.1, 127.0.0.2 etc.
> on common systems.  If you handle 127.0.0.2 as local, you apply side

127.0.0.2 is not local on any of my systems. The only exceptions
are some Linux boxen that I did not ask to do so.

I welcome suggestions, maybe even code fragments, that will allow
an MTA to correctly recognize user@[ip.address] as local, as required
by the SMTP RFC.

> On Thu, Sep 06, 2001 at 04:17:49PM +0200, Matthias Andree wrote:
> > I'm not sure where and why you deduce the idea this is about MTA loop
> > detection or peer recognition.
> 
> Because it's the obvious reason to start to be aware about networking
> configuration, and all MTAs known to me try to do it.
> 
> All other reasons are absolutely artificial.

It is perfectly OK for an MTA to make a distinction between local
subnets and the rest of the Internet.

I welcome suggestions, maybe even code fragments, that will allow
an MTA to correctly recognize the subnetworks that the machine is
attached to.

	Wietse