2.9 Azure Storage Accounts and Services

Quick Answer: A standard general-purpose v2 Azure Storage account can host four services: Blob (objects), Files (SMB/NFS shares), Queue (64 KB messages), and Table (NoSQL). Redundancy options range from LRS (replication within one datacenter) to GZRS (replication across zones and a secondary region). Blob tiers are Hot, Cool, Cold, Archive. On AZ-900, match the keyword in the question to the service: "shared drive" = Files, "objects/backups" = Blob, "region failure" = GRS/GZRS, "zone failure" = ZRS/GZRS.

What a Storage Account Is

A storage account is a top-level container that gives your data a globally unique namespace. The account name (3-24 lowercase letters and numbers) must be unique across all of Azure because it becomes part of a public endpoint URL. Each service gets its own endpoint built from that name:

A single account can host all four services at once. Storage service endpoints support HTTPS; whether a client can reach data depends on network rules, authentication, and authorization. Access methods vary by service and include account keys, shared access signatures (SAS), and Microsoft Entra ID identities.

Account Types

On the Exam: Standard general-purpose v2 is a common choice when you need supported standard storage services in one account. It can host the four standard services, but available redundancy and access-tier combinations depend on the service and region; for example, Archive blobs do not support ZRS or GZRS, and Azure Files does not support RA-GRS or RA-GZRS. Premium account types target specialized workloads.

The Four Data Services

Blob Storage (objects)

Blob (Binary Large Object) Storage holds unstructured data: images, video, backups, logs, documents. There are three blob types: block blobs for general files up to 190.7 TiB, append blobs optimized for logging, and page blobs (up to 8 TiB) that back virtual hard disks for VMs.

Access Tiers

A worked example: you retain 10 TB of compliance logs for at least 180 days and can wait hours when an old file is requested. Archive may reduce storage charges if retrieval and early-deletion costs still make the total favorable. If logs need immediate access, choose an online tier instead. An archived blob is offline until rehydrated to Hot, Cool, or Cold; rehydration may take hours.

Azure Files (shared drives)

Azure Files provides fully managed file shares reachable over SMB (Server Message Block) and NFS (Network File System). Multiple machines mount the same share like a network drive. Azure File Sync caches a cloud share on on-premises Windows servers for hybrid access. Reach for Files whenever a question says "replace a file server," "shared drive," or "lift-and-shift an app that expects SMB."

Queue and Table Storage

• Queue Storage holds messages (up to 64 KB each) for asynchronous, decoupled communication between app components — a web tier drops work; a worker tier picks it up later, so each scales independently.
• Table Storage is a schemaless NoSQL key-value store for large volumes of structured-but-non-relational data. Azure Cosmos DB for Table is an alternative with global distribution and other feature differences; choose by requirements.

Redundancy Options

RA-GRS and RA-GZRS add read access to the secondary region without a failover, subject to access controls. With GRS/GZRS, secondary access follows a supported failover, which may be customer-managed or Microsoft-managed. Memory hooks: a zone-failure requirement suggests ZRS or GZRS; a region-failure requirement suggests GRS or GZRS; a secondary-read requirement suggests an RA variant. Read access is distinct from durability.

Migration and Movement Tools

For a large transfer with limited bandwidth, compare an available Data Box device with network-transfer tools such as AzCopy; device capacity and availability depend on the current model and region.