Azure Data Migration Tools: AzCopy, Data Box, and Azure Migrate

Azure gives you five distinct ways to get data or workloads into the cloud, and each one is built for a different combination of volume, bandwidth, and automation need. AzCopy scripts online transfers, Storage Explorer handles occasional manual browsing, Azure File Sync keeps a file share synchronized on an ongoing basis, Data Box ships physical hardware when bandwidth can’t handle the volume, and Azure Migrate assesses and orchestrates the move of whole servers and databases. Picking the wrong one on the exam usually means confusing “how do I copy files” with “how do I move a workload.”

AzCopy: command-line, scriptable, unattended

AzCopy is a command-line utility purpose-built for high-throughput, scripted movement of data into, out of, and between Azure Storage accounts. Because it runs entirely from a terminal with no graphical component, it’s the tool of choice for anything that needs to run unattended — a nightly cron job uploading research datasets, a pipeline step that pushes build artifacts into a blob container, or any workflow where no one is sitting at a keyboard to click through a wizard. AzCopy also supports resuming interrupted transfers automatically, which matters for long-running jobs over unreliable links.

One AzCopy capability worth knowing by name is the sync command. Rather than re-uploading an entire folder every run, azcopy sync compares the source and destination and transfers only files that are new or changed since the last run — the right answer whenever a scenario describes a recurring job that shouldn’t waste time and bandwidth re-copying everything each time.

Azure Storage Explorer: graphical, manual, occasional

Azure Storage Explorer is a free, cross-platform desktop application (Windows, macOS, and Linux) for visually browsing and managing blobs, file shares, queues, and tables. It’s the direct opposite of AzCopy in intent: point-and-click rather than scripted, ideal for an administrator who occasionally needs to inspect a container, drag a handful of files over, or manage access keys, but has no need to automate anything. Whenever a scenario explicitly rules out scripting or asks for a graphical interface with no coding, Storage Explorer is the fit — AzCopy would technically move the same files, but it doesn’t satisfy a “no scripting” requirement.

Azure File Sync: continuous, cached, multi-site

Azure File Sync solves a different problem entirely: keeping an on-premises Windows Server file share continuously synchronized with an Azure file share, while caching only the actively used files locally and tiering the rest to the cloud. This is the answer whenever a scenario describes branch offices running low on local disk space that still need employees to keep mapping drives with SMB exactly as before — File Sync centralizes the full data set in Azure while each local server caches only what’s currently being touched, reclaiming disk space transparently. It’s not a one-time copy tool like AzCopy; it’s an ongoing, bidirectional relationship between the on-premises server and the cloud.

Azure Data Box family: offline, physical, bandwidth-constrained

When the volume of data to move is too large for a network transfer to be practical — because the link is too slow, too expensive, or both — Azure ships you a physical, ruggedized appliance instead. You load your data onto the device locally, ship it back to Microsoft, and Microsoft uploads it into your storage account from their datacenter. The family scales by capacity:

• Azure Data Box — the standard, rack-mountable appliance for bulk transfers in the tens-of-terabytes range, too large for portable disks but well below petabyte scale.
• Azure Data Box Disk — individual rugged portable SSDs, sized for smaller volumes, roughly tens of terabytes, when a full rack-mount appliance would be overkill.
• Azure Data Box Heavy — a much larger, wheeled enclosure built specifically for petabyte-scale transfers that no other Data Box option can hold in a single shipment.

A related but distinct offering, the Azure Import/Export service, lets a customer ship their own hard drives to an Azure datacenter for upload, rather than using a Microsoft-supplied appliance — both are physical-shipping methods rather than network transfer, which is the distinction the exam cares about. Once that shipped data lands in a storage account, it’s just as eligible as anything uploaded over the network for a lower-cost access tier such as Cool or Archive if it won’t be touched right away.

Azure Migrate: assessment and orchestration for workloads

Azure Migrate is not a data-copying tool at all — it’s a centralized hub for discovering on-premises servers, databases, and virtual machines, assessing their readiness and estimated Azure cost, and then orchestrating the actual migration. Whenever a scenario is about moving whole VMs or right-sizing hundreds of on-premises servers before committing to a migration plan, Azure Migrate is the answer, not AzCopy or Data Box — those two move files and blobs, not running virtual machines. For servers that stay partly on-premises after the move, Azure Arc extends that same management plane to the hybrid resources Migrate doesn’t fully relocate.

Comparing the tools

Tool	Interface	Best for	Data type
AzCopy	Command line	Scripted, unattended, repeatable transfers	Files/blobs
Storage Explorer	GUI	Occasional manual browsing and transfers	Files/blobs
Azure File Sync	Background service	Ongoing sync with local caching	File shares
Data Box family	Physical appliance	Large volumes, limited bandwidth	Bulk files
Azure Migrate	Web-based hub	Assessing and moving servers/VMs	Workloads

How the AZ-900 exam tests this

• A scenario stresses “no manual steps” or “runs unattended overnight.” That phrasing always points to AzCopy, since Storage Explorer requires an interactive session.
• A scenario gives a data volume and a slow or costly internet link. The exam wants you to recognize that network tools (AzCopy, Storage Explorer, File Sync) can’t solve a bandwidth problem, and route you to the right member of the Data Box family based on the stated volume — Disk for smaller loads, standard Data Box for mid-size, Heavy for petabyte scale.
• A scenario combines migrating virtual machines and moving a large volume of file data in the same sentence. This tests whether you know Azure Migrate and Data Box solve two different halves of the problem and are usually paired together, rather than expecting one tool to do both.
• A scenario mentions branch offices, local caching, or “keep using the same mapped drive.” That’s File Sync’s signature pattern, distinguishing it from a one-time AzCopy job.

Once you can separate “moving files” from “moving workloads” and “online” from “offline,” these tool names stop being a memorization exercise — practice this with real AZ-900 questions to see how the exam layers volume, bandwidth, and automation constraints into a single stem. These migration tools work hand in hand with the storage account types they’re moving data into, so it’s worth pairing this with Azure Storage services and account types and with Azure Storage redundancy options for how that migrated data stays durable once it lands.

Quick reference

• AzCopy: command-line, scriptable, unattended; azcopy sync transfers only new or changed files.
• Storage Explorer: free graphical desktop app for manual, occasional browsing and transfers — no scripting.
• Azure File Sync: continuous sync between an on-premises file server and Azure Files, with local caching and cloud tiering.
• Data Box: standard rack-mount appliance for tens of terabytes; Data Box Disk for smaller loads; Data Box Heavy for petabyte scale.
• Azure Import/Export: customer ships their own drives to an Azure datacenter, distinct from Microsoft-supplied Data Box hardware.
• Azure Migrate: discovery, assessment, and orchestration for migrating on-premises servers, databases, and VMs — not a file-copy tool.
• Large VM migrations often pair Azure Migrate (for the workloads) with Data Box (for the bulk file data) when bandwidth is limited.