Merge pull request #124951 from ehvs/hevs/gpu-sku

added steps for SKU

Author: Court72

articles/openshift/howto-gpu-workloads.md

@@ -6,7 +6,7 @@ ms.author: johnmarc
 ms.service: azure-redhat-openshift
 keywords: aro, gpu, openshift, red hat
 ms.topic: how-to
-ms.date: 12/15/2023
+ms.date: 11/29/2024
 ms.custom: template-how-to
 ---
 
@@ -188,6 +188,36 @@ ARO uses Kubernetes MachineSet to create machine sets. The procedure below expla
 
 1. Verify the other data in the yaml file.
 
+#### Ensure the correct SKU is set
+
+Depending on the image used for the machine set, both values for `image.sku` and `image.version` must be set accordingly. This is to ensure if generation 1 or 2 virtual machine for Hyper-V will be used. See [here](/windows-server/virtualization/hyper-v/plan/should-i-create-a-generation-1-or-2-virtual-machine-in-hyper-v) for more information.
+
+Example:
+
+If using `Standard_NC4as_T4_v3`, both versions are supported. As mentioned in [Feature support](/azure/virtual-machines/sizes/gpu-accelerated/ncast4v3-series?tabs=sizebasic#feature-support). In this case, no changes are required.
+
+If using `Standard_NC24ads_A100_v4`, only **Generation 2 VM** is [supported](/azure/virtual-machines/sizes/gpu-accelerated/nca100v4-series?tabs=sizebasic#feature-support).
+In this case, the `image.sku` value must follow the equivalent `v2` version of the image that corresponds to the cluster's original `image.sku`. For this example, the value will be `v410-v2`.
+
+This can be found using the following command:
+
+```bash
+az vm image list --architecture x64 -o table --all --offer aro4 --publisher azureopenshift
+```
+
+```
+Filtered output:
+
+SKU      VERSION
+-------  ---------------
+v410-v2  410.84.20220125
+aro_410  410.84.20220125
+```
+
+If the cluster was created with the base SKU image `aro_410`, and the same value is kept in the machine set, it will fail with the following error:
+```
+failure sending request for machine myworkernode: cannot create vm: compute.VirtualMachinesClient#CreateOrUpdate: Failure sending request: StatusCode=400 -- Original Error: Code="BadRequest" Message="The selected VM size 'Standard_NC24ads_A100_v4' cannot boot Hypervisor Generation '1'.
+```
 #### Create GPU machine set
 
 Use the following steps to create the new GPU machine. It may take 10-15 minutes to provision a new GPU machine. If this step fails, sign in to [Azure portal](https://portal.azure.com) and ensure there are no availability issues. To do so, go to **Virtual Machines** and search for the worker name you created previously to see the status of VMs.