Comment 7 for bug 1641224

As far as I can see, there is no RackSpace specific override. OpenStack provider is checking constraints against "flavor.Name". See https://github.com/juju/juju/blob/89a200d3f68420250d18cb08f2fda4e58c7baaa3/provider/openstack/provider.go#L651

To be true, even if this would be fixed, targetting "compute1-4" flavour would fail since in the RackSpace cloud, the "compute" and "memory" class flavours do not have ephemeral root disks and could be booted from a Cinder volume only. See https://github.com/juju/juju/blob/89a200d3f68420250d18cb08f2fda4e58c7baaa3/provider/rackspace/flavors.go#L23

Nevertheless, I believe that this bug should be re-opened. There is no easy way to target standard/general purpose flavours using only CPU and memory constraints. 2 GB General Purpose instance type (id general1-2) has 2 GB RAM and 2 CPUs like 2GB Standard Instance (id 4). The size is of a disk is different, but "general1-2" instance type has a configurable disk size which creates ambiguity. Scheduler might interpret --constraints "mem=2GB cpu=2 root-disk=80GB" as a request for "general1-2" instance type with 80 GB disk.