I am the co-admin of a subscription in Microsoft Azure which contains a notification hub. I want to set alerts on the various error metrics of the notification hub. However, I can't find a way to set alerts in the classical portal and these error metrics are not visible in the new portal. When I clicked on the Settings tab in the classical portal, the page which opened up didn't have any button for setting alerts.
Has the alert support been taken off the azure classical portal?
I afraid that it is not possible (i have tried to find that info as well) for a moment. For alerting, you should use Azure Management Services (click on the Operation Logs) and there is no Notification Hub in the drop-down menu of the supported services.
There is the FAQ stating that there is no alerts for NH out-of-the-box, but the third-party services may apply.
If 3rd party services are not the option, you may implement your own functionality - NH provides API and you may notify your team if something happened using that REST API.