Veeam ONE Monitor Client shows the "No data available" message on performance charts for different metrics:
Cause
The account used for collecting data from vCenter Server or ESX(i) host does not have sufficient permissions on the virtual server.
Solution
To resolve this issue, make sure the permissions are granted for the user account that is used to connect to a corresponding virtual infrastructure object.
More Information
If you have any questions or problems, please contact Veeam Support.