The IPv6 standards define an algorithm to generate temporary random IPv6 addresses that are less traceable over time. This is documented in RFC 4941 “Privacy Extensions for Stateless Address Autoconfiguration in IPv6”. The following instructions apply to a network card called eth0, if your is different, then change to suit.
To enable the use of Privacy Extension under Ubuntu and other Debian derivatives, you need to edit the following.
Edit you sysctl.conf file.
sudo nano /etc/sysctl.conf
Append the following.
net.ipv6.conf.eth0.use_tempaddr = 2 net.ipv6.conf.all.use_tempaddr = 2 net.ipv6.conf.default.use_tempaddr = 2
At this point, you need to restart your network or reboot, to do the former type the folling at the prompt.
sudo /etc/init.d/networking restart
Now if you type ifconfig eth0 at the prompt, you should get something that looks similar to this.
ifconfig eth0 eth0 Link encap:Ethernet HWaddr 00:03:1d:04:67:f0 inet addr:192.168.1.10 Bcast:192.168.1.255 Mask:255.255.255.0 inet6 addr: 2001:DB8:XXXX:XXXX:XXXX:XXXX:XXXX:XXXX/64 Scope:Global inet6 addr: fe80::203:1dff:fe04:67f0/64 Scope:Link inet6 addr: 2001:DB8:XXXX:XXXX:XXXX:XXXX:XXXX:XXXX/64 Scope:Global UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:92741 errors:0 dropped:0 overruns:0 frame:0 TX packets:118185 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:100 RX bytes:15268311 (15.2 MB) TX bytes:23369787 (23.3 MB) Memory:fdee0000-fdf00000
As you can see, eth0 now has 2 IPv6 addresses, one of which is randomly generated and will change and is used externally. The other which will stay the same can be addressed over the internet (by yourself or friends if you want to share).
Ubuntu forum IPv6 privacy extension
IPv6 Related Stuff: Enabling IPv6 Pricacy Extensions on Ubuntu Linux
IPv6 privacy extensions on Linux
Mice and Men Support – Enabling IPv6 Privacy Extensions.
Enabling IPv6 privacy extensions on Ubuntu