Jails, loopback interfaces and sendmail

[Gregory Shapiro]

>> 8.12.7/8.12.7   2002/12/29
> yes, that's not from stone age:(

Well, the way things move, it almost is.  :)

> Have you ever thought about having those files changed just for
> FreeBSD?  Or had there been porblems on FreeBSD systems with localhost
> as well?

Now that you mention it, we are already using separate FreeBSD files in
src/etc/sendmail/freebsd{,.submit}.mc so I can do something different
for FreeBSD.  I think we are still in code slush and not freeze for 8.0.
I'll double check and if so, make the change tonight (with a note in
UPDATING).  As I recall, nobody reported a problem resolving localhost
under FreeBSD.

> Has it been a special time with localhost and IPv6 that caused
> problems as 2002 has been rather late in terms of sendmail and
> resolver etc.  What had started to cause those problems?

Sadly, that didn't stick in my memory.  The MTA handles IPv4 fallback
on a failed IPv6 connection if an IPv4 address is available so I don't
think IPv6 enters into it.  If I recall correctly, it was simply a
matter of localhost returning h_errno == HOST_NOT_FOUND or the resolver
returning NXDOMAIN.  I'll check with Claus to see if he remembers.

Another scenario that I still see today (as owner of localhost.org)
is sites that have a bogus 'domain' or 'search' such that the
lookup for 'localhost' returns information about 'localhost.com' or
'localhost.org'.  I've tried to improve that situation by mapping
localhost.org's A record to 127.0.0.1.  Unfortunately, the owners of
localhost.com and localhost.net (as well as possibly everything other
TLD) have not done the same.