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I see a support case opened for the same. I am summarizing the details provided by support team here for the benefit of community, so that it can help others in the community looking for help on similar topics.
Requirement: Looking for a solution to monitor the VM's based on uptime via a dashboard.
The current capabilities of Azure Monitor VM insights does not have this as a out of box solution.
So it is suggested to use Azure Monitor Workbooks to build your custom dashboards. Reference article (https://github.com/azure-ad-b2c/siem).
To mention, Workbooks provide a flexible canvas for data analysis and the creation of rich visual reports within the Azure portal. More details can be found in below docs:
https://learn.microsoft.com/en-us/azure/azure-monitor/visualize/workbooks-overview
https://learn.microsoft.com/en-us/azure/azure-monitor/visualize/workbooks-grid-visualizations.
You can also check the video tutorials available here.
Workbook can use KQL queries that transform the underlying resource data to select a result set that can visualized as text, charts, or grids. For building a query to calculate the uptime, you may leverage the queries mentioned in the link here.
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