Add AKS troubleshooting section

Add AKS troubleshooting section to resolve issue pytorch#803

kubernetes/AKS/README.md

@@ -289,3 +289,21 @@ Or if resource group is no longer needed, use the az group delete command to rem
 ```
 az group delete --name myResourceGroup --yes --no-wait
 ```
+
+## Troubleshooting
+
+
+  **Troubleshooting Azure Cli login**
+
+  Az login command will open your default browser, it will do so and load an Azure sign-in page.
+  Otherwise, open a browser page at https://aka.ms/devicelogin and enter the authorization code displayed in your terminal.
+  If no web browser is available or the web browser fails to open, use device code flow with az login --use-device-code.
+  Or you can login with your credential in command line, more details, see https://docs.microsoft.com/en-us/cli/azure/authenticate-azure-cli.
+
+  **Troubleshooting Azure resource for AKS cluster creation**
+
+  * Check AKS availble region, https://azure.microsoft.com/en-us/global-infrastructure/services/?products=kubernetes-service
+  * Check AKS quota and VM size limitation, https://docs.microsoft.com/en-us/azure/aks/quotas-skus-regions
+  * Check whether your subscription has enough quota to create AKS cluster, https://docs.microsoft.com/en-us/azure/networking/check-usage-against-limits
+
+  **For more AKS troubleshooting, please visit https://docs.microsoft.com/en-us/azure/aks/troubleshooting**