Preparing to unpack .../cloud-init_0.7.5-0ubuntu1.15_all.deb ...

AZURE: this instance uses an unstable instance ID. Cloud-init will
    migrate the instance ID from:
            851663c0fea04a769f746831fe1d6e1e
        to:
            6F3C8573-4172-924A-B6BA-86A31C316AB4
    For more information about this change, please see:
    https://bugs.launchpad.net/bug/1506187
    https://azure.microsoft.com/en-us/blog/accessing-and-using-azure-vm-unique-id

Unpacking cloud-init (0.7.5-0ubuntu1.15) over (0.7.5-0ubuntu1.14) ...