Comment 23 for bug 1068756

ok. so some updates.
Ben fixed this in the cloud image build process via [1] (commit [2]), and limited the change to utopic+.
The fix was done by adding a file /etc/sysctl.d/99-cloudimg-ipv6.conf

The problem with this change is described in bug 1352255 and bug 994931. If ipv6 addresses are already configured, then setting the 'net.ipv6.conf.all.use_tempaddr' will remove the configured addresses.

So to actually fix this right, I suggest that the build proces:
 * dpkg-divert /etc/sysctl.d/10-ipv6-privacy.conf to /etc/sysctl.d/10-ipv6-privacy.conf.disabled
 * add a file /etc/sysctl.d/10-ipv6-privacy.conf.README that explains that and how the user could re-enable it (un-dpkg-divert it).

--
[1] http://bazaar.launchpad.net/~ubuntu-on-ec2/vmbuilder/automated-ec2-builds/view/head:/live-config/common/hooks/060-ipv6.chroot
[2] http://bazaar.launchpad.net/~ubuntu-on-ec2/vmbuilder/automated-ec2-builds/revision/646