OK, I've given this some thought. I think we can probably just modify the default, as udev rules will ensure that it exists.
As we'll be matching udev rules, we'll need to modify it to /dev/disk/azure/resource in places where we don't ship udev rules with cloud-init (i.e. trusty), and to /dev/disk/cloud/azure_resource in places that we do (e.g. xenial and later).
We _could_ backport the cloud-init udev rules to trusty, but I don't think we need to.
OK, I've given this some thought. I think we can probably just modify the default, as udev rules will ensure that it exists.
As we'll be matching udev rules, we'll need to modify it to /dev/disk/ azure/resource in places where we don't ship udev rules with cloud-init (i.e. trusty), and to /dev/disk/ cloud/azure_ resource in places that we do (e.g. xenial and later).
We _could_ backport the cloud-init udev rules to trusty, but I don't think we need to.