Hi,
Private endpoints do not have a status metric. As you can see from the available metrics they only have Bytes In and Bytes out. So from technical point of view the private endpoint cannot be done. If you want you can set alert to monitor the bytes in and out but keep in mind that means that you need some constant traffic passing the private endpoint. Best is to set some Connection monitor that monitors this SaaS application from VM that is in the same virtual network as the private endpoint.
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