Constraints 'cores=8 mem=32G' fails on azure/westus2

[Léo Schoukroun]

I'm struggling to understand instance selection with Azure.

For example if I deploy my app with --constraints 'cores=8 mem=32G' on region azure/westus2, it tries to provision a Standard_DC8s_v3 but fails because it does not support Ubuntu 22.04_lts gen1: The selected VM size 'Standard_DC8s_v3' cannot boot Hypervisor Generation '1'. If this was a Create operation please check that the Hypervisor Generation of the Image matches the Hypervisor Generation of the selected VM Size. If this was an Update operation please select a Hypervisor Generation '1' VM Size. For more information, see https://aka.ms/azuregen2vm

By trying to create manually on Azure I can confirm that Standard_DC8s_v3 with 22.04_lts gen1 on westus2 can not be provisioned.

Also if I run with --constraints 'instance-type=Standard_DC8s_v3' it fails with invalid constraint value: instance-type=Standard_DC8s_v3 and it is indeed not in the list so why would Juju pick this with the previous command?

With --constraints 'cores=8 mem=32G' on region azure/francecentral works fine and provisions a Standard B2ls v2 BUT its running 22_04-lts gen1.

My goal is to be able to run --constraints 'cores=8 mem=32G' on any region and make it work everytime (I don't really care if it ends up being a gen1 or gen2). Thanks in advance 🙏

I am running with Juju 3.2.4 on both client and controller.

[Joseph Phillips (manadart)]

This instance type can be run with a 22.04 base in the "centralus" region.

Based on a look through the logic, when we assemble the resources list, we make no use of `Locations` or `LocationInfo` in the `ResourceSKU` list that we get back.

This is from the SDK:

// READ-ONLY; A list of locations and availability zones in those locations where the SKU is available.
LocationInfo []*ResourceSKULocationInfo `json:"locationInfo,omitempty" azure:"ro"`

// READ-ONLY; The set of locations that the SKU is available.
Locations []*string `json:"locations,omitempty" azure:"ro"`

I believe we're missing a filter here.

[Jack Shaw (jack-shaw)]

Hi, are you still experiencing this?

I haven't been able to replicate this bug

```
$ juju version
3.2.4-ubuntu-amd64
$ juju bootstrap azure/westus2
...
$ juju add-model m
Added 'm' model on azure/westus2 with credential 'juju-qa-azure' for user 'admin'
$ juju add-machine --constraints 'cores=8 mem=32G'
created machine 0
[wait a few moments]
$ juju status
Model Controller Cloud/Region Version SLA Timestamp
m azure-westus2 azure/westus2 3.2.4 unsupported 11:10:34Z

Machine State Address Inst id Base AZ Message
0 started 20.72.216.39 machine-0 ubuntu@22.04
```

`machine-0` here was created with type Standard_D8_v5

Also, as a side, Juju 3.2 is no longer supported by the Juju team. We would recommend you migrate your workloads to 3.3, regardless. I have been unable to replicate this bug on 3.3 as well