Aside from ::/128 (undefined address) and ::1/128 (local loopback), the entirety of ::/96 was reserved for ipv4-compatible addresses and had been deprecated for

Aside from ::/128 (undefined address) and ::1/128 (local loopback), the entirety of ::/96 was reserved for ipv4-compatible addresses and had been deprecated for a while [1] It is safe to assume that they won't be allocated in the future. You can easily assign them to your loopback interface. e.g. on linux: $ ip addr add ::2/128 dev lo You will then be able to use them over loopback just like ::1, and can populate your /etc/hosts file accordingly. $ ping6 -c 1 ::2 PING ::2(::2) 56 data bytes 64 bytes from ::2: icmp_seq=1 ttl=64 time=0.078 ms 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 0.078/0.078/0.078/0.000 ms [1] http://tools.ietf.org/html/rfc4291#section-4 http://tools.ietf.org/html/rfc4291#section-4 EDIT: formatting.