On mail principles

[a at zeos.net]

On Wed, Jun 07, 2006 at 05:43:23PM -0400, Charles Swiger wrote:
> On Jun 7, 2006, at 1:20 PM, a at zeos.net wrote:
> >But this way is bad for local purposes: my MTA's diagnostic messages are sent
> >trough internet or lost at all, e. g. when my ADSL is in down.
> >(Moreover, my letters sent to other local users have non-local "envelope from"
> >address. Then local mail begin to go through external MTA.)
> >
> >What to do in such a situation?
> 
> See the sendmail documentation [1] on MASQUERADE_AS().
> 
> --
> -Chuck
> 
> [1]: /usr/share/sendmail/cf/README, or check the FAQ from www.sendmail.org...

That is not a proper feature because of different local users can use world 
mail addresses with different hostnames. But masquerading is good only for 
one domain.