Renewing ACS Kubernetes cluster
Updating azure.json is not enough.
In order to update your cluster with new credentials, you should use az aks update-credentials command
az aks update-credentials \ --resource-group myResourceGroup \ --name myAKSCluster \ --reset-service-principal \ --service-principal $SP_ID \ --client-secret $SP_SECRETAfter that cluster autoscaler will use updated principal for the new instances
Update:
For acs cluster you have to manually update service principal on each worker node.
Or you may use custom script extension, which you can integrate with Azure Resource Manager template or run by Azure Virtual Machines REST API