The following reply was made to PR bin/30745; it has been noted by GNATS.

From: fredb@immanent.net (Frederick Bruckman)
To: "Martin Husemann <martin@duskware.de>:"@netbsd.org
Cc: gnats-bugs@netbsd.org, netbsd-bugs@netbsd.org
Subject: Re: bin/30745: ntp dies on IPv4-only kernels
Date: Sat, 3 Sep 2005 11:45:20 -0500 (CDT)

 In article <20050714030200.ABC5A63B121@narn.netbsd.org>,
 	Martin Husemann <martin@duskware.de> writes:
 > 
 > When upgrading a machine to 3.0_BETA or -current, ntpd might stop working.
 > If you have a time server in your /etc/ntp.conf that has a IPv6 address,
 > like the former public server at ntp.univ-lyon1.fr:
 > 
 > ntp.univ-lyon1.fr is an alias for dns.univ-lyon1.fr.
 > dns.univ-lyon1.fr has address 134.214.100.6
 > ntp.univ-lyon1.fr is an alias for dns.univ-lyon1.fr.
 > dns.univ-lyon1.fr has IPv6 address 2001:660:5001:100::6
 > ntp.univ-lyon1.fr is an alias for dns.univ-lyon1.fr.
 > 
 > and you are running a IPv4 only kernel, ntpd logs:
 > 
 > sendto(2001:660:5001:100::6): Address family not supported by protocol family
 > 
 > and dies!
 > 
 > I'm sure this is part of the conspiracy to force everyone into IPv6 - but
 > please start pushing ISPs first instead of users.
 
 Ha! Indeed. I'm starting to think that global IPv6 is never going
 to happen.
 
 You can put "-4 " before the name of the server to force IPv4.
 Does that help?
 
 There's an open request to have ntpd try all addresses in turn:
 
   https://ntp.isc.org/bugs/show_bug.cgi?id=334
 
 A more general solution would be to train the resolver to do IPv4
 only.  In lieu of that, if you can run a nameserver, the latest
 version of bind9 has a "-4" option, which is "politically correct"
 by virtue of there also being a "-6" option.
 
 -- 
 Frederick