How to order a Databox extract when the blob is bigger than the maximum size of the largest databox

Question

How to order a Databox extract when the blob is bigger than the maximum size of the largest databox

Sendall, Richard 0

Hello,

I have a large amount of data held in Azure Storage Account Cold tier that I would like to extract to on-premise using a Databox. I've been told that the data in the blob is larger than the biggest databox that is available, that a blob cannot be split across multiple databoxes. What's the best way to proceed with this?

Many thanks.

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2 answers

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Answer 1

Christos Panagiotidis 3,551

What you were told is only partly correct. Data Box does not split one blob object across devices, but a single Azure block blob is smaller than Data Box 120 or 525 usable capacity. The likely issue is the container or total dataset size.

Create multiple export orders and partition data by container or blob-name prefix. For each order, supply an XML blob list with distinct BlobPath or BlobPathPrefix entries; Microsoft also provides a script to generate manifests for multiple devices. Ensure manifests do not overlap and each selection fits its device.

Data Box export supports Hot and Cool blobs, so first change selected Cold-tier blobs to Cool or Hot and wait for tier changes to finish. Review retrieval and early-deletion charges. After delivery, validate copy and verbose logs before deleting Azure data. If device availability or the active-order limit blocks the plan, contact Microsoft Support.

Sendall, Richard 0 Reputation points

2026-07-21T15:59:36.29+00:00

Many thanks for your help. Apologies, but I'm not very familiar with Azure. The total data size I want to export I believe is about 660TB which is larger than the DataBox 525. When I log into the Storage Account using Storage Explorer, I see the Storage Accounts -> Blob Containers -> Container and then in the container, I see 4 "directories" with the data I want inside them. It is that container I want which is about 660TB big.

I don't follow what you mean "BlobPath" and "BlobPathPrefix"? How do I generate the manifest to ensure it fits on the DataBox?

Thanks.

Answer 2

Hello Sendall, Richard

Thanks for contacting us about moving your Azure Storage data to your on-premises environment with Azure Data Box.

From what you shared, the data is stored in the Archive tier, and the total size is larger than what a single Azure Data Box can handle. Please note that Azure Data Box Export cannot export data directly from the Archive tier. The archived blobs need to be rehydrated to the Cool or Hot access tier first before they can be included in a Data Box export. Depending on your retention period, rehydration, retrieval, and possible early deletion charges may also apply.

Because the overall data volume exceeds the capacity of one Data Box, the best approach is to set up multiple Data Box export orders and split the data into smaller sets. You can do this by organizing the data by containers, virtual directories, blob prefixes, or other logical groupings. Each export job should include a unique set of blobs and stay within the supported capacity of the selected Data Box device.

If you have any very large individual blobs, please confirm their size. Azure Data Box cannot split a single blob across multiple devices, so network-based transfer methods may need to be used in those cases.

Let us know if you have any questions or need help with the rehydration and export planning process.

Reference Doc: https://docs.azure.cn/en-us/databox/data-box-disk-limits