Credential Format

Azure Service Operator supports four different styles of authentication today.

Each section below dives into one of these authentication options, including examples for how to set it up and use it at the different credential scopes.

Azure Workload Identity

See Azure Workload Identity for details about the workload identity project.

Workload identity (with Managed Identity) is the recommended authentication mode for production use-cases.

Prerequisites

  1. An existing Azure Service Principal or Managed Identity. The setup is the same regardless of which you choose.
  2. The Azure CLI.
  3. An OIDC endpoint associated with your cluster. See how to enable OIDC on AKS.

Use the following Bash commands to set the environment variables containing the workload identity secret (customize with your values):

export AZURE_CLIENT_ID="00000000-0000-0000-0000-00000000000"       # The client ID (sometimes called App Id) of the Service Principal, or the Client ID of the Managed Identity with which you are using Workload Identity.
export AZURE_SUBSCRIPTION_ID="00000000-0000-0000-0000-00000000000" # The Azure Subscription ID the identity is in.
export AZURE_TENANT_ID="00000000-0000-0000-0000-00000000000"       # The Azure AAD Tenant the identity/subscription is associated with.
export SERVICE_ACCOUNT_ISSUER="https://oidc.prod-aks.azure.com/00000000-0000-0000-0000-00000000000/" # The OIDC endpoint for your cluster in this example AKS

Configure trust

Establish trust between your OIDC issuer URL and the backing Service Principal or Managed Identity. See how it works for details.

Set the following additional environment variables:

export MI_RESOURCE_GROUP="my-rg"  # The resource group containing the managed identity that will be used by ASO
export MI_NAME="my-mi"            # The name of the managed identity that will be used by ASO

Create the Federated Identity Credential registering your service account with AAD:

az identity federated-credential create --name aso-federated-credential --identity-name ${MI_NAME} --resource-group ${MI_RESOURCE_GROUP} --issuer ${SERVICE_ACCOUNT_ISSUER} --subject "system:serviceaccount:azureserviceoperator-system:azureserviceoperator-default" --audiences "api://AzureADTokenExchange"

export APPLICATION_OBJECT_ID="$(az ad app show --id ${AZURE_CLIENT_ID} --query id -otsv)"

cat <<EOF > params.json
{
  "name": "aso-federated-credential",
  "issuer": "${SERVICE_ACCOUNT_ISSUER}",
  "subject": "system:serviceaccount:azureserviceoperator-system:azureserviceoperator-default",
  "description": "Kubernetes service account federated credential",
  "audiences": [
    "api://AzureADTokenExchange"
  ]
}
EOF

az ad app federated-credential create --id ${APPLICATION_OBJECT_ID} --parameters @params.json

Create the secret

If installing ASO for the first time, you can pass these values via Helm arguments:

helm upgrade --install --devel aso2 aso2/azure-service-operator \
        --create-namespace \
        --namespace=azureserviceoperator-system \
        --set azureSubscriptionID=$AZURE_SUBSCRIPTION_ID \
        --set azureTenantID=$AZURE_TENANT_ID \
        --set azureClientID=$AZURE_CLIENT_ID \
        --set useWorkloadIdentityAuth=true \
        --set crdPattern='resources.azure.com/*;containerservice.azure.com/*;keyvault.azure.com/*;managedidentity.azure.com/*;eventhub.azure.com/*'

See CRD management for more details about crdPattern.

Otherwise, create or update the aso-controller-settings secret:

cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: Secret
metadata:
 name: aso-controller-settings
 namespace: azureserviceoperator-system
stringData:
 AZURE_SUBSCRIPTION_ID: "$AZURE_SUBSCRIPTION_ID"
 AZURE_TENANT_ID: "$AZURE_TENANT_ID"
 AZURE_CLIENT_ID: "$AZURE_CLIENT_ID"
 USE_WORKLOAD_IDENTITY_AUTH: "true"
EOF

Note: The aso-controller-settings secret contains more configuration than just the global credential. If ASO was already installed on your cluster and you are updating the aso-controller-settings secret, ensure that other values in that secret are not being overwritten.

Create the aso-credential secret in your namespace:

cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: Secret
metadata:
 name: aso-credential
 namespace: my-namespace
stringData:
 AZURE_SUBSCRIPTION_ID: "$AZURE_SUBSCRIPTION_ID"
 AZURE_TENANT_ID:    "$AZURE_TENANT_ID"
 AZURE_CLIENT_ID:    "$AZURE_CLIENT_ID"
 AUTH_MODE:          "workloadidentity"
EOF

Note: Each credential (both namespaced and per-resource) you create must have a trust relationship between your OIDC issuer URL and the backing Service Principal or Managed Identity. See how to configure trust for more details.

Create a per-resource secret. We’ll use my-resource-secret:

cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: Secret
metadata:
 name: my-resource-secret
 namespace: my-namespace
stringData:
 AZURE_SUBSCRIPTION_ID: "$AZURE_SUBSCRIPTION_ID"
 AZURE_TENANT_ID:    "$AZURE_TENANT_ID"
 AZURE_CLIENT_ID:    "$AZURE_CLIENT_ID"
 AUTH_MODE:          "workloadidentity"
EOF

Create the ASO resource referring to my-resource-secret. We show a ResourceGroup here, but any ASO resource will work.

cat <<EOF | kubectl apply -f -
apiVersion: resources.azure.com/v1api20200601
kind: ResourceGroup
metadata:
  name: aso-sample-rg
  namespace: default
  annotations:
    serviceoperator.azure.com/credential-from: my-resource-secret
spec:
  location: westcentralus
EOF

Note: Each credential (both namespaced and per-resource) you create must have a trust relationship between your OIDC issuer URL and the backing Service Principal or Managed Identity. See how to configure trust for more details.

Service Principal using a Client Secret

Prerequisites

  1. An existing Azure Service Principal.

To use Service Principal authentication with client secret, create a secret with the AZURE_CLIENT_ID and AZURE_CLIENT_SECRET keys set.

For more information about Service Principals, see Work with Azure service principal using the Azure CLI. The AZURE_CLIENT_ID is sometimes also called the App ID. The AZURE_CLIENT_SECRET is the “password” returned by the command in the previously linked documentation.

Use the following Bash commands to set the environment variables containing the service principal secret (customize with your values):

export AZURE_CLIENT_ID="00000000-0000-0000-0000-00000000000"       # The client ID (sometimes called App Id) of the Service Principal.
export AZURE_CLIENT_SECRET="00000000-0000-0000-0000-00000000000"   # The client secret of the Service Principal.
export AZURE_SUBSCRIPTION_ID="00000000-0000-0000-0000-00000000000" # The Azure Subscription ID the identity is in.
export AZURE_TENANT_ID="00000000-0000-0000-0000-00000000000"       # The Azure AAD Tenant the identity/subscription is associated with.

Create the secret

If installing ASO for the first time, you can pass these values via Helm arguments:

helm upgrade --install --devel aso2 aso2/azure-service-operator \
        --create-namespace \
        --namespace=azureserviceoperator-system \
        --set azureSubscriptionID=$AZURE_SUBSCRIPTION_ID \
        --set azureTenantID=$AZURE_TENANT_ID \
        --set azureClientID=$AZURE_CLIENT_ID \
        --set azureClientSecret=$AZURE_CLIENT_SECRET \
        --set crdPattern='resources.azure.com/*;containerservice.azure.com/*;keyvault.azure.com/*;managedidentity.azure.com/*;eventhub.azure.com/*'

See CRD management for more details about crdPattern.

Otherwise, create or update the aso-controller-settings secret:

cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: Secret
metadata:
 name: aso-controller-settings
 namespace: azureserviceoperator-system
stringData:
 AZURE_SUBSCRIPTION_ID: "$AZURE_SUBSCRIPTION_ID"
 AZURE_TENANT_ID: "$AZURE_TENANT_ID"
 AZURE_CLIENT_ID: "$AZURE_CLIENT_ID"
 AZURE_CLIENT_SECRET: "$AZURE_CLIENT_SECRET"
EOF

Note: The aso-controller-settings secret contains more configuration than just the global credential. If ASO was already installed on your cluster and you are updating the aso-controller-settings secret, ensure that other values in that secret are not being overwritten.

Create the aso-credential secret in your namespace:

cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: Secret
metadata:
 name: aso-credential
 namespace: my-namespace
stringData:
 AZURE_SUBSCRIPTION_ID: "$AZURE_SUBSCRIPTION_ID"
 AZURE_TENANT_ID: "$AZURE_TENANT_ID"
 AZURE_CLIENT_ID: "$AZURE_CLIENT_ID"
 AZURE_CLIENT_SECRET: "$AZURE_CLIENT_SECRET"
EOF

Create a per-resource secret. We’ll use my-resource-secret:

cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: Secret
metadata:
 name: my-resource-secret
 namespace: my-namespace
stringData:
 AZURE_SUBSCRIPTION_ID: "$AZURE_SUBSCRIPTION_ID"
 AZURE_TENANT_ID: "$AZURE_TENANT_ID"
 AZURE_CLIENT_ID: "$AZURE_CLIENT_ID"
 AZURE_CLIENT_SECRET: "$AZURE_CLIENT_SECRET"
EOF

Create the ASO resource referring to my-resource-secret. We show a ResourceGroup here, but any ASO resource will work.

cat <<EOF | kubectl apply -f -
apiVersion: resources.azure.com/v1api20200601
kind: ResourceGroup
metadata:
  name: aso-sample-rg
  namespace: default
  annotation:
    serviceoperator.azure.com/credential-from: my-resource-secret
spec:
  location: westcentralus
EOF

Service Principal using a Client Certificate

Prerequisites

  1. An existing Azure Service Principal.
  2. X.509 certificate in ASCII format such as PEM, CER, or DER.

To use Service Principal authentication via client certificate, create a secret with the AZURE_CLIENT_ID, AZURE_CLIENT_CERTIFICATE and AZURE_CLIENT_CERTIFICATE_PASSWORD(optional) keys set.

For more information about creating Service Principals with certificate, see creating an Azure Service Principal using certificate based authentication. The AZURE_CLIENT_ID is sometimes also called the App ID. The AZURE_CLIENT_CERTIFICATE is the certificate returned by the command in the previously linked documentation.

Use the following Bash commands to set the environment variables containing the service principal certificate secret (customize with your values):

export AZURE_CLIENT_ID="00000000-0000-0000-0000-00000000000"          # The client ID (sometimes called App Id) of the Service Principal.
export AZURE_SUBSCRIPTION_ID="00000000-0000-0000-0000-00000000000"    # The Azure Subscription ID the identity is in.
export AZURE_TENANT_ID="00000000-0000-0000-0000-00000000000"          # The Azure AAD Tenant the identity/subscription is associated with.
export AZURE_CLIENT_CERTIFICATE=`cat path/to/certFile.pem`                    # The client certificate of the Service Principal.
export AZURE_CLIENT_CERTIFICATE_PASSWORD="myPrivateKeyValue"          # The private key for the above certificate (optional)

Create the secret

If installing ASO for the first time, you can pass these values via Helm arguments:

helm upgrade --install --devel aso2 aso2/azure-service-operator \
        --create-namespace \
        --namespace=azureserviceoperator-system \
        --set azureSubscriptionID=$AZURE_SUBSCRIPTION_ID \
        --set azureTenantID=$AZURE_TENANT_ID \
        --set azureClientID=$AZURE_CLIENT_ID \
        --set azureClientCertificatePassword=$AZURE_CLIENT_CERTIFICATE_PASSWORD \
        --set crdPattern='resources.azure.com/*;containerservice.azure.com/*;keyvault.azure.com/*;managedidentity.azure.com/*;eventhub.azure.com/*'

See CRD management for more details about crdPattern.

Otherwise, create or update the aso-controller-settings secret:

cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: Secret
metadata:
 name: aso-controller-settings
 namespace: azureserviceoperator-system
stringData:
 AZURE_SUBSCRIPTION_ID: "$AZURE_SUBSCRIPTION_ID"
 AZURE_TENANT_ID: "$AZURE_TENANT_ID"
 AZURE_CLIENT_ID: "$AZURE_CLIENT_ID"
 AZURE_CLIENT_CERTIFICATE: "$AZURE_CLIENT_CERTIFICATE"
 AZURE_CLIENT_CERTIFICATE_PASSWORD: "$AZURE_CLIENT_CERTIFICATE_PASSWORD"
EOF

Note: The aso-controller-settings secret contains more configuration than just the global credential. If ASO was already installed on your cluster and you are updating the aso-controller-settings secret, ensure that other values in that secret are not being overwritten.

Create the aso-credential secret in your namespace:

cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: Secret
metadata:
 name: aso-credential
 namespace: my-namespace
stringData:
 AZURE_SUBSCRIPTION_ID: "$AZURE_SUBSCRIPTION_ID"
 AZURE_TENANT_ID: "$AZURE_TENANT_ID"
 AZURE_CLIENT_ID: "$AZURE_CLIENT_ID"
 AZURE_CLIENT_CERTIFICATE: "$AZURE_CLIENT_CERTIFICATE"
 AZURE_CLIENT_CERTIFICATE_PASSWORD: "$AZURE_CLIENT_CERTIFICATE_PASSWORD"
EOF

Create a per-resource secret. We’ll use my-resource-secret:

cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: Secret
metadata:
 name: my-resource-secret
 namespace: my-namespace
stringData:
 AZURE_SUBSCRIPTION_ID: "$AZURE_SUBSCRIPTION_ID"
 AZURE_TENANT_ID: "$AZURE_TENANT_ID"
 AZURE_CLIENT_ID: "$AZURE_CLIENT_ID"
 AZURE_CLIENT_CERTIFICATE: "$AZURE_CLIENT_CERTIFICATE"
 AZURE_CLIENT_CERTIFICATE_PASSWORD: "$AZURE_CLIENT_CERTIFICATE_PASSWORD"
EOF

Create the ASO resource referring to my-resource-secret. We show a ResourceGroup here, but any ASO resource will work.

cat <<EOF | kubectl apply -f -
apiVersion: resources.azure.com/v1api20200601
kind: ResourceGroup
metadata:
  name: aso-sample-rg
  namespace: default
  annotation:
    serviceoperator.azure.com/credential-from: my-resource-secret
spec:
  location: westcentralus
EOF

[Deprecated] Managed Identity (aad-pod-identity)

This authentication mechanism still works but is deprecated. See Azure Workload Identity for the new way

Prerequisites

  1. An existing Azure Managed Identity.
  2. aad-pod-identity installed into your cluster. If you are running ASO on an Azure Kubernetes Service (AKS) cluster, you can instead use the integrated aad-pod-identity.

First, set the following environment variables:

export IDENTITY_RESOURCE_GROUP="myrg"                              # The resource group containing the managed identity.
export IDENTITY_NAME="myidentity"                                  # The name of the identity.
export AZURE_SUBSCRIPTION_ID="00000000-0000-0000-0000-00000000000" # The Azure Subscription ID the identity is in.
export AZURE_TENANT_ID="00000000-0000-0000-0000-00000000000"       # The Azure AAD Tenant the identity/subscription is associated with.

Use the az cli to get some more details about the identity to use:

export IDENTITY_CLIENT_ID="$(az identity show -g ${IDENTITY_RESOURCE_GROUP} -n ${IDENTITY_NAME} --query clientId -otsv)"
export IDENTITY_RESOURCE_ID="$(az identity show -g ${IDENTITY_RESOURCE_GROUP} -n ${IDENTITY_NAME} --query id -otsv)"

Create the secret

If installing ASO for the first time, you can pass these values via Helm arguments:

helm upgrade --install --devel aso2 aso2/azure-service-operator \
     --create-namespace \
     --namespace=azureserviceoperator-system \
     --set azureSubscriptionID=$AZURE_SUBSCRIPTION_ID \
     --set aadPodIdentity.enable=true \
     --set aadPodIdentity.azureManagedIdentityResourceId=${IDENTITY_RESOURCE_ID} \
     --set azureClientID=${IDENTITY_CLIENT_ID} \
     --set crdPattern='resources.azure.com/*;containerservice.azure.com/*;keyvault.azure.com/*;managedidentity.azure.com/*;eventhub.azure.com/*'

See CRD management for more details about crdPattern.

Otherwise, if deploying manually:

Deploy an AzureIdentity:

cat <<EOF | kubectl apply -f -
apiVersion: "aadpodidentity.k8s.io/v1"
kind: AzureIdentity
metadata:
  name: aso-identity
  namespace: azureserviceoperator-system
spec:
  type: 0
  resourceID: ${IDENTITY_RESOURCE_ID}
  clientID: ${IDENTITY_CLIENT_ID}
EOF

Deploy an AzureIdentityBinding to bind this identity to the Azure Service Operator manager pod:

cat <<EOF | kubectl apply -f -
apiVersion: "aadpodidentity.k8s.io/v1"
kind: AzureIdentityBinding
metadata:
  name: aso-identity-binding
  namespace: azureserviceoperator-system
spec:
  azureIdentity: aso-identity
  selector: aso-manager-binding
EOF

Create or update the aso-controller-settings secret:

cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: Secret
metadata:
 name: aso-controller-settings
 namespace: azureserviceoperator-system
stringData:
 AZURE_SUBSCRIPTION_ID: "$AZURE_SUBSCRIPTION_ID"
 AZURE_TENANT_ID: "$AZURE_TENANT_ID"
 AZURE_CLIENT_ID: "$IDENTITY_CLIENT_ID"
EOF

Note: The aso-controller-settings secret contains more configuration than just the global credential. If ASO was already installed on your cluster and you are updating the aso-controller-settings secret, ensure that other values in that secret are not being overwritten.

Deploy an AzureIdentity:

cat <<EOF | kubectl apply -f -
apiVersion: "aadpodidentity.k8s.io/v1"
kind: AzureIdentity
metadata:
  name: aso-identity
  namespace: azureserviceoperator-system
spec:
  type: 0
  resourceID: ${IDENTITY_RESOURCE_ID}
  clientID: ${IDENTITY_CLIENT_ID}
EOF

Deploy an AzureIdentityBinding to bind this identity to the Azure Service Operator manager pod:

cat <<EOF | kubectl apply -f -
apiVersion: "aadpodidentity.k8s.io/v1"
kind: AzureIdentityBinding
metadata:
  name: aso-identity-binding
  namespace: azureserviceoperator-system
spec:
  azureIdentity: aso-identity
  selector: aso-manager-binding
EOF

Create the aso-credential secret in your namespace:

cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: Secret
metadata:
 name: aso-credential
 namespace: my-namespace
stringData:
 AZURE_SUBSCRIPTION_ID: "$AZURE_SUBSCRIPTION_ID"
 AZURE_TENANT_ID:       "$AZURE_TENANT_ID"
 AZURE_CLIENT_ID:       "$IDENTITY_CLIENT_ID"
 AUTH_MODE:             "podidentity"
EOF

Deploy an AzureIdentity:

cat <<EOF | kubectl apply -f -
apiVersion: "aadpodidentity.k8s.io/v1"
kind: AzureIdentity
metadata:
  name: aso-identity
  namespace: azureserviceoperator-system
spec:
  type: 0
  resourceID: ${IDENTITY_RESOURCE_ID}
  clientID: ${IDENTITY_CLIENT_ID}
EOF

Deploy an AzureIdentityBinding to bind this identity to the Azure Service Operator manager pod:

cat <<EOF | kubectl apply -f -
apiVersion: "aadpodidentity.k8s.io/v1"
kind: AzureIdentityBinding
metadata:
  name: aso-identity-binding
  namespace: azureserviceoperator-system
spec:
  azureIdentity: aso-identity
  selector: aso-manager-binding
EOF

Create a per-resource secret. We’ll use my-resource-secret:

cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: Secret
metadata:
 name: my-resource-secret
 namespace: my-namespace
stringData:
 AZURE_SUBSCRIPTION_ID: "$AZURE_SUBSCRIPTION_ID"
 AZURE_TENANT_ID:       "$AZURE_TENANT_ID"
 AZURE_CLIENT_ID:       "$IDENTITY_CLIENT_ID"
 AUTH_MODE:             "podidentity"
EOF

Create the ASO resource referring to my-resource-secret. We show a ResourceGroup here, but any ASO resource will work.

cat <<EOF | kubectl apply -f -
apiVersion: resources.azure.com/v1api20200601
kind: ResourceGroup
metadata:
  name: aso-sample-rg
  namespace: default
  annotations:
    serviceoperator.azure.com/credential-from: my-resource-secret
spec:
  location: westcentralus
EOF