Hi Handinata Tanudjaja ,
Yes, this behavior is expected. When you create a new disk from a snapshot of an Azure Disk Encryption enabled disk, the encryption settings do not automatically carry over to the new disk. You need to re-enable ADE on the new disk after it has been created
To ensure the new disk has ADE enabled,
1.Attach the new disk to a VM.
2.Enable ADE on the new disk using the Azure portal, PowerShell, or CLI.
This process ensures that the new disk is encrypted and meets your security requirements.
For more information:
https://learn.microsoft.com/en-us/azure/virtual-machines/image-version-encryption?tabs=PowerShell
https://learn.microsoft.com/en-us/azure/virtual-machines/disk-encryption-overview
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