Content-MD5 Header calculation when using Azure DataBox

Question

I am planning a file migration to Azure Blob Storage using Azure Databox. (For reference, I plan on using the SMB model instead of the NFS/Rest).

Is the Content-MD5 calculated in that scenario, or should I calculate locally and explicitly set the x-ms-blob-content-md5 blob property after the restore into the SA?

Thanks

Answer 1

When transferring files to Azure Blob Storage using the SMB model with Azure Databox, the Content-MD5 is not calculated during the transfer. As a result, it is recommended to calculate the Content-MD5 locally and set the x-ms-blob-content-md5 blob property explicitly after the restore into the storage account.

You can use the below code to calculate the Content-MD5 locally and set the x-ms-blob-content-md5 blob property using the Azure Storage Python SDK.

Code:

from azure.storage.blob import BlobServiceClient,ContentSettings
import hashlib

blob_service_client = BlobServiceClient.from_connection_string("<Your connection string>")
blob_client = blob_service_client.get_blob_client(container="sample",blob="vm1example.txt")
with open(r"/path/to/local/file", "rb") as f:
    content = f.read()
    content_md5 = hashlib.md5(content).digest()
content_settings = ContentSettings(content_md5=content_md5)
blob_client.set_http_headers(content_settings=content_settings)

Output:

Reference:
Manage properties and metadata for a blob with Python - Azure Storage | Microsoft Learn