Azure AKS Node Pool
Deploys a node pool into an existing Azure Kubernetes Service (AKS) cluster with configurable VM size, node count, autoscaling, availability zones, OS type, pool mode, and Spot VM pricing. The component creates a containerservice.AgentPool resource attached to the referenced parent cluster.
What Gets Created
When you deploy an AzureAksNodePool resource, OpenMCF provisions:
- Agent Pool — a
containerservice.AgentPoolresource in the specified resource group and parent AKS cluster, configured with the chosen VM size, initial node count, OS type, and pool mode - Autoscaling — cluster autoscaler configuration on the pool when
autoscalingis provided, with configurable minimum and maximum node counts - Availability Zone Spread — node distribution across the specified Azure availability zones for high availability
- Spot VM Configuration — when
spotEnabledis true, the pool uses Spot priority with a Delete eviction policy and pay-up-to-regular-price bidding
Prerequisites
- Azure credentials configured via environment variables or OpenMCF provider config
- An AKS cluster that the node pool will be added to (can reference an AzureAksCluster resource)
- An Azure Resource Group where the parent cluster resides (can reference an AzureResourceGroup resource)
Quick Start
Create a file nodepool.yaml:
apiVersion: azure.openmcf.org/v1
kind: AzureAksNodePool
metadata:
name: worker-pool
labels:
openmcf.org/provisioner: pulumi
pulumi.openmcf.org/organization: my-org
pulumi.openmcf.org/project: my-project
pulumi.openmcf.org/stack.name: dev.AzureAksNodePool.worker-pool
spec:
clusterName: my-aks-cluster
vmSize: Standard_D4s_v3
initialNodeCount: 3
resourceGroup: my-rg
Deploy:
openmcf apply -f nodepool.yaml
This creates a 3-node User-mode Linux node pool using Standard_D4s_v3 VMs with no autoscaling and no availability zone pinning.
Configuration Reference
Required Fields
| Field | Type | Description | Validation |
|---|---|---|---|
clusterName | StringValueOrRef | Name of the parent AKS cluster. Can reference an AzureAksCluster resource via valueFrom. | Required |
vmSize | string | VM size (SKU) for nodes in this pool (e.g., Standard_D4s_v3). Determines the CPU and memory of each node. | Required |
initialNodeCount | int32 | Number of nodes to create initially. When autoscaling is off, this is the fixed node count. | Required, must be greater than 0 |
resourceGroup | StringValueOrRef | Azure Resource Group where the parent cluster resides. Can reference an AzureResourceGroup resource via valueFrom. | Required |
Optional Fields
| Field | Type | Default | Description |
|---|---|---|---|
autoscaling | object | none | Autoscaling configuration. When set, cluster autoscaler is enabled for this pool. Contains minNodes (uint32, >= 0) and maxNodes (uint32, > 0). |
availabilityZones | string[] | [] | Zones to spread nodes across for high availability. Valid values: "1", "2", "3". If specified, at least 2 zones are required. |
osType | enum | LINUX | Operating system type. Values: LINUX, WINDOWS. Windows pools require a cluster with Windows support. |
mode | enum | USER | Pool mode. SYSTEM pools host critical cluster components (CoreDNS, metrics-server), must be Linux, and cannot scale to zero. USER pools run application workloads, can be Linux or Windows, and can scale to zero. |
spotEnabled | bool | false | Use Spot (preemptible) VMs to reduce cost. Spot pools use a Delete eviction policy and pay up to the regular on-demand price. Cannot be used with System mode pools. |
Examples
Basic User Pool
A simple application workload pool with a fixed node count:
apiVersion: azure.openmcf.org/v1
kind: AzureAksNodePool
metadata:
name: app-pool
labels:
openmcf.org/provisioner: pulumi
pulumi.openmcf.org/organization: my-org
pulumi.openmcf.org/project: my-project
pulumi.openmcf.org/stack.name: dev.AzureAksNodePool.app-pool
spec:
clusterName: my-aks-cluster
vmSize: Standard_D2s_v3
initialNodeCount: 2
resourceGroup: dev-rg
Autoscaling Pool with Availability Zones
A production pool that scales between 2 and 10 nodes across three availability zones:
apiVersion: azure.openmcf.org/v1
kind: AzureAksNodePool
metadata:
name: prod-pool
labels:
openmcf.org/provisioner: pulumi
pulumi.openmcf.org/organization: my-org
pulumi.openmcf.org/project: my-project
pulumi.openmcf.org/stack.name: prod.AzureAksNodePool.prod-pool
spec:
clusterName: prod-cluster
vmSize: Standard_D4s_v3
initialNodeCount: 3
resourceGroup: prod-rg
autoscaling:
minNodes: 2
maxNodes: 10
availabilityZones:
- "1"
- "2"
- "3"
Spot Instance Pool for Batch Workloads
A cost-optimized pool using Spot VMs that can scale to zero when idle:
apiVersion: azure.openmcf.org/v1
kind: AzureAksNodePool
metadata:
name: batch-pool
labels:
openmcf.org/provisioner: pulumi
pulumi.openmcf.org/organization: my-org
pulumi.openmcf.org/project: my-project
pulumi.openmcf.org/stack.name: prod.AzureAksNodePool.batch-pool
spec:
clusterName: prod-cluster
vmSize: Standard_D8s_v3
initialNodeCount: 1
resourceGroup: prod-rg
spotEnabled: true
autoscaling:
minNodes: 0
maxNodes: 20
availabilityZones:
- "1"
- "2"
- "3"
System Pool
A System-mode pool to host critical cluster components. System pools must be Linux and cannot scale to zero:
apiVersion: azure.openmcf.org/v1
kind: AzureAksNodePool
metadata:
name: system-pool
labels:
openmcf.org/provisioner: pulumi
pulumi.openmcf.org/organization: my-org
pulumi.openmcf.org/project: my-project
pulumi.openmcf.org/stack.name: prod.AzureAksNodePool.system-pool
spec:
clusterName: prod-cluster
vmSize: Standard_D2s_v3
initialNodeCount: 3
resourceGroup: prod-rg
mode: SYSTEM
autoscaling:
minNodes: 2
maxNodes: 5
availabilityZones:
- "1"
- "2"
- "3"
Using Foreign Key References
Reference OpenMCF-managed resources instead of hardcoding names:
apiVersion: azure.openmcf.org/v1
kind: AzureAksNodePool
metadata:
name: ref-pool
labels:
openmcf.org/provisioner: pulumi
pulumi.openmcf.org/organization: my-org
pulumi.openmcf.org/project: my-project
pulumi.openmcf.org/stack.name: prod.AzureAksNodePool.ref-pool
spec:
clusterName:
valueFrom:
kind: AzureAksCluster
name: prod-cluster
field: metadata.name
vmSize: Standard_D4s_v3
initialNodeCount: 3
resourceGroup:
valueFrom:
kind: AzureResourceGroup
name: prod-rg
field: status.outputs.resource_group_name
autoscaling:
minNodes: 2
maxNodes: 8
Stack Outputs
After deployment, the following outputs are available in status.outputs:
| Output | Type | Description |
|---|---|---|
nodePoolName | string | Name of the node pool in AKS. Typically matches the resource metadata.name. |
agentPoolResourceId | string | Azure Resource Manager ID of the created Agent Pool resource. |
maxPodsPerNode | uint32 | Maximum number of pods that can run on each node of this pool. Determined by AKS based on network configuration and VM size. |
Related Components
- AzureAksCluster — provides the parent cluster that this node pool is added to
- AzureResourceGroup — provides the resource group where the parent cluster resides
- AzureVpc — provides the virtual network and subnets used by the AKS cluster
- AzureSubnet — provides subnets that can be assigned to node pools for network isolation
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