If you know the exact ID of the dashboard you wish to display, then you can use this property to force that dashboard to be displayed.

Manage a read-only dashboard.

If you have decided to show a read-only copy of a dashboard to your users which is managed by your organization, then you can set the dashboardId value to the same as the parentDashboardId. Be sure to correctly manage the permissions by setting the scope to read in your identity config.

Managing multiple dashboards per user.

You can use the dashboard manager hook to create multiple child copies of a parent dashboard, and then provide the ID of the dashboard that you wish to display via this dashboardId prop to render it.