Comment 4 for bug 1377005

I got a very similar response by deploying a regular dual-stack node, commenting out it network interface's DHCPv4 config in /etc/network/interfaces, and rebooting.

Something very strange happened: the network interface comes up with IPv6 only, which in itself is what you'd expect. But it gets only a link-local address! The cloud-init log was full of failed attempts to read the instance-id from the (correct-looking) MAAS metadata URL: name or service unknown.