Hello Stavros
Good day!
The "Disk Used Bytes (Avg)" metric in AKS is calculated by aggregating the disk space used in bytes by the device across all nodes in the AKS cluster. The metric is calculated by using the Azure Monitor Logs tables.
It is possible that the size of the pods and the cluster nodes do not match the value of the "Disk Used Bytes (Avg)" metric because the metric is an average of the disk space used by the device across all nodes in the AKS cluster.
For more details on the "Disk Used Bytes (Avg)" metric and other metrics in AKS, you can refer to the following documentation:
https://learn.microsoft.com/en-us/azure/aks/monitor-aks-reference
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