PF_UNSPEC queries are made. While there change the default from inet6
first then inet4 to inet4 first then inet6, this prevents the many
people with IPv4 only connectivity from constantly trying to contact
IPv6 addresses, and also unbreaks many ports who don't use getaddrinfo
right.
ok deraadt@, plenty of cheering in the room wrt the idea, not loud
enough complaining from the v6 crowd.
"options edns0" in /etc/resolv.conf will enable the behavior. no behavior
change if you don't have the line. see resolv.conf(5) for more details.
EDNS0 is useful for avoiding TCP DNS queries/replies on larger DNS responses.
also, draft-ietf-dnsext-message-size-* plans to mandate EDNS0 support for DNS
clients that support IPv6 transport.