There are scenarios where workloads (pods) need to run on virtual machines (VMs) with a specific architecture to meet application or performance requirements. While in Ocean clusters for AWS this can be achieved by selecting an AMI with the required architecture, Ocean AKS does not allow choosing a specific image during AKS cluster creation. This article explains how to configure architecture-specific VMs in an Ocean AKS environment.

1. Create or edit a Virtual Node Group (VNG):

   • In your Ocean AKS cluster, create a new VNG manually or import and edit an existing node pool configuration.
      

2. Add architecture filters in the VNG JSON configuration:

   • Include the vmSizes argument as shown below:

     "vmSizes": {
        "filters": {
           "architectures": [
               "x86_64"
           ],
           "series": []
        }
     }

      

   • The architectures array supports these values:

     • x86_64 (includes both intel64 and amd64.)

     • intel64

     • amd64

     • arm64

3. Specify VM series that supports the chosen architecture:

   • Use the series argument within the filters to ensure only compatible VM sizes are selected.

Example

To launch VMs with the ARM64 architecture from the Dps_V5 series:

"vmSizes": {
    "filters": {
        "architectures": [
            "arm64"
        ],
        "series": [
            "Dps_V5"
        ]
    }
}

When this configuration is applied to your VNG, Ocean AKS will provision nodes supporting the specified architecture for your workloads.

Outcome

The cluster will launch VMs from the selected series that match the desired architecture, ensuring workloads run on compatible hardware.