Some suggestions from: rwatson, Ruben de Groot <mail25@bzerk.org>
/etc/ip6addrctl.conf. following sample of ip6addrctl.conf is a good default: #Prefix Precedence Label ::1/128 50 0 ::/0 40 1 2002::/16 30 2 ::/96 20 3 ::ffff:0:0/96 10 4