AKS: Persistent Volume Claim with an Azure File Storage protected with a Private Endpoint
Categories:
4 minute read
This post will show you the steps you’ll have to take to deploy an Azure Files Storage with a Private Endpoint and use it to create volumes for an Azure Kubernetes Service cluster:
Create a bicep file to declare the Azure resources
You’ll have to declare the following resources:
- A VNET with 2 subnets. One for the private endpoint and the other for the AKS cluster.
- An Azure Files storage.
- A Private Endpoint for the storage.
- A Private DNS Zone and Private DNS Zone Group.
- A link between the Private DNS Zone to the VNET.
- An AKS cluster.
- A role assignment to add the kubelet identity of the cluster as a Contributor to the Storage Account.
in a main.bicep file with the following contents:
param sa_name string = 'akscsisa'
param aks_name string = 'akscsimsft'
// Create the VNET
resource vnet 'Microsoft.Network/virtualNetworks@2020-11-01' = {
name: 'private-network'
location: 'westeurope'
properties: {
addressSpace: {
addressPrefixes: [
'10.0.0.0/8'
]
}
subnets: [
{
name: 'endpoint'
properties: {
addressPrefix: '10.241.0.0/16'
serviceEndpoints: []
delegations: []
privateEndpointNetworkPolicies: 'Disabled'
privateLinkServiceNetworkPolicies: 'Enabled'
}
}
{
name: 'aks'
properties: {
addressPrefix: '10.240.0.0/16'
serviceEndpoints: []
delegations: []
privateEndpointNetworkPolicies: 'Enabled'
privateLinkServiceNetworkPolicies: 'Enabled'
}
}
]
enableDdosProtection: false
}
}
// Create the File Storage Account
resource sa 'Microsoft.Storage/storageAccounts@2021-01-01' = {
name: sa_name
location: 'westeurope'
sku: {
name: 'Premium_LRS'
tier: 'Premium'
}
kind: 'FileStorage'
properties: {
minimumTlsVersion: 'TLS1_0'
allowBlobPublicAccess: false
isHnsEnabled: false
networkAcls: {
bypass: 'AzureServices'
virtualNetworkRules: []
ipRules: []
defaultAction: 'Deny'
}
supportsHttpsTrafficOnly: true
accessTier: 'Hot'
}
}
// Create the Private Enpoint
resource private_endpoint 'Microsoft.Network/privateEndpoints@2020-11-01' = {
name: 'sa-endpoint'
location: 'westeurope'
properties: {
privateLinkServiceConnections: [
{
name: 'sa-privateserviceconnection'
properties: {
privateLinkServiceId: sa.id
groupIds: [
'file'
]
}
}
]
subnet: {
id: '${vnet.id}/subnets/endpoint'
}
}
}
// Create the Private DNS Zone
resource dns 'Microsoft.Network/privateDnsZones@2018-09-01' = {
name: 'privatelink.file.core.windows.net'
location: 'global'
}
// Link the Private DNS Zone with the VNET
resource vnet_dns_link 'Microsoft.Network/privateDnsZones/virtualNetworkLinks@2018-09-01' = {
name: '${dns.name}/test'
location: 'global'
properties: {
registrationEnabled: false
virtualNetwork: {
id: vnet.id
}
}
}
// Create Private DNS Zone Group
resource dns_group 'Microsoft.Network/privateEndpoints/privateDnsZoneGroups@2020-11-01' = {
name: '${private_endpoint.name}/default'
properties: {
privateDnsZoneConfigs: [
{
name: 'privatelink-file-core-windows-net'
properties: {
privateDnsZoneId: dns.id
}
}
]
}
}
// Create AKS cluster
resource aks 'Microsoft.ContainerService/managedClusters@2021-02-01' = {
name: aks_name
location: 'westeurope'
identity: {
type: 'SystemAssigned'
}
properties: {
kubernetesVersion: '1.19.9'
dnsPrefix: aks_name
agentPoolProfiles: [
{
name: 'default'
count: 1
vmSize: 'Standard_D2s_v3'
osDiskSizeGB: 30
osDiskType: 'Ephemeral'
vnetSubnetID: '${vnet.id}/subnets/aks'
type: 'VirtualMachineScaleSets'
orchestratorVersion: '1.19.9'
osType: 'Linux'
mode: 'System'
}
]
servicePrincipalProfile: {
clientId: 'msi'
}
addonProfiles: {
kubeDashboard: {
enabled: false
}
}
enableRBAC: true
networkProfile: {
networkPlugin: 'kubenet'
networkPolicy: 'calico'
loadBalancerSku: 'standard'
podCidr: '10.244.0.0/16'
serviceCidr: '10.0.0.0/16'
dnsServiceIP: '10.0.0.10'
dockerBridgeCidr: '172.17.0.1/16'
}
apiServerAccessProfile: {
enablePrivateCluster: false
}
}
}
// Built-in Role Definition IDs
// https://docs.microsoft.com/en-us/azure/role-based-access-control/built-in-roles
var contributor = '/subscriptions/${subscription().subscriptionId}/providers/Microsoft.Authorization/roleDefinitions/b24988ac-6180-42a0-ab88-20f7382dd24c'
// Set AKS kubelet Identity as SA Contributor
resource aks_kubelet_sa_contributor 'Microsoft.Authorization/roleAssignments@2020-04-01-preview' = {
name: guid('${aks_name}_kubelet_sa_contributor')
scope: sa
properties: {
principalId: reference(aks.id, '2021-02-01', 'Full').properties.identityProfile['kubeletidentity'].objectId
roleDefinitionId: contributor
}
}
Deploy the Azure resources
Run the following commands to deploy the Azure resources:
az group create -n private-pvc-test -l westeurope
az deployment group create -f ./main.bicep -g private-pvc-test
After 10 minutes or so you’ll have all resources up and running.
Install Azure CSI Driver
The Azure Files Container Storage Interface (CSI) driver can be installed on the cluster so Azure Kubernetes Service (AKS) can manage the lifecycle of Azure Files shares.
To install the driver run:
az aks get-credentials -n akscsimsft -g private-pvc-test --overwrite-existing
curl -skSL https://raw.githubusercontent.com/kubernetes-sigs/azurefile-csi-driver/v1.5.0/deploy/install-driver.sh | bash -s v1.5.0 --
and check the pods status:
kubectl -n kube-system get pod -o wide --watch -l app=csi-azurefile-controller
kubectl -n kube-system get pod -o wide --watch -l app=csi-azurefile-node
You should find instances of csi-azurefile-controller and csi-azurefile-node running without issues.
Create a Storage Class
Create a file named: storageclass-azurefile-csi.yaml with the following yaml:
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
name: azurefile-csi
provisioner: file.csi.azure.com
allowVolumeExpansion: true
parameters:
resourceGroup: <resourceGroup> # optional, only set this when storage account is not in the same resource group as agent node
storageAccount: <storageAccountName>
# Check driver parameters here:
# https://github.com/kubernetes-sigs/azurefile-csi-driver/blob/master/docs/driver-parameters.md
server: <storageAccountName>.privatelink.file.core.windows.net
reclaimPolicy: Delete
volumeBindingMode: Immediate
mountOptions:
- dir_mode=0777
- file_mode=0777
- uid=0
- gid=0
- mfsymlinks
- cache=strict # https://linux.die.net/man/8/mount.cifs
- nosharesock # reduce probability of reconnect race
- actimeo=30 # reduce latency for metadata-heavy workload
Remember to replace the values of <resourceGroup>
and <storageAccountName>
with the ones used in the previous deployment. (i.e. private-pvc-test and akscsisa)
Now deploy the Storage Class to the cluster:
kubectl apply -f storageclass-azurefile-csi.yaml
Create a Private Volume Claim
Create a Private Volume Claim that uses the storage class. Create pvc.yaml with the following contents:
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
name: my-azurefile
spec:
accessModes:
- ReadWriteMany
storageClassName: azurefile-csi
resources:
requests:
storage: 100Gi
Deploy the Private Volume Claim to the cluster and check that everything is ok:
kubectl apply -f pvc.yaml
k get pvc
Now feel free to try and mount a volume using the Private Volume Claim: my-azurefile
Hope it helps!!!
Please find a bicep based sample here or if you prefer terraform here
References: