An Azure service that is used to collect, analyze, and act on telemetry data from Azure and on-premises environments.
I answer Myself. It is not supported the vpn connections' resorce health alert. It just developing now. It doesn't have any plans of add the function.
I think it is because the connections' reousrce health doesn't report any activity logs.
https://learn.microsoft.com/en-us/azure/service-health/resource-health-alert-monitor-guide
I attach the answer but It is korean.
it is the translated one.
Resource Health Alerts for VPN Connections do not appear to be supported at this time.
I don't know the exact date, but they are currently preparing to apply and will be completed soon.
Resource Health operates on the activity log and alerts must be generated with a category designated as 'Resource Health'.
Create Resource Health Alerts using Azure portal - Azure Service Health | Microsoft Learn
However, the activity log based on the category is not supported as I said, so the alert cannot be generated at this time.
Please let me know if you have any additional inquiries or lack of explanation.
Thank you.