<p>In Azure K8s service, you can scale up the node pool but only we define the min and max nodes.
When i check the node pool scale set scale settings, i found it set to manual.
So i assume that the Node Pool auto scale does't rely on the belonging scale set, but i wonder, can we just rely on the scale set auto scale with the several metric roles instead of the very limited Node Pool scale settings ?</p>

<p>The AKS autoscaling works slightly different as the VMSS autoscaling.</p>
<p>From the <a href="https://learn.microsoft.com/en-us/azure/aks/cluster-autoscaler" rel="nofollow noreferrer">official docs</a>:</p>
<blockquote>
<p>The cluster autoscaler watches for pods that can't be scheduled on
nodes because of resource constraints. The cluster then automatically
increases the number of nodes.</p>
</blockquote>
<p>The AKS autoscaler is tightly coupled with the control plane and the kube-scheduler, so it takes resource requests and limits into account that is far the better scaling method as the VMSS autoscaler (for k8s workload) that is anyway not supported for AKS:</p>
<blockquote>
<p>The cluster autoscaler is a Kubernetes component. Although the AKS
cluster uses a virtual machine scale set for the nodes, don't manually
enable or edit settings for scale set autoscale in the Azure portal or
using the Azure CLI.</p>
</blockquote>
