Azure Storage Services – File, Object, and Data Lake Storage

Azure Storage Services

The DP-900 exam covers Azure Files, Azure Blob storage, ADLS, and Azure Table storage. Because Azure Table storage was covered in Chapter 3, the following sections will focus on Azure Files, Azure Blob storage, and ADLS.

Azure Files

Azure Files is a storage service that allows organizations to build fully managed file shares in Azure. File shares deployed through Azure Files can be accessed using the SMB protocol on standard and premium storage accounts or the NFS protocol on premium storage accounts. The service organizes data in a hierarchical folder structure and is typically used to replace or complement on-premises file shares. Along with the benefits that are native to Azure storage accounts such as offloading hardware management and global redundancy, data stored in an Azure file share can be accessed from anywhere in the world.

File shares created in Azure Files can be mounted concurrently to a VM in the cloud or on a user’s local machine for access. SMB file shares can be mounted to Windows, Linux, or macOS devices. NFS file shares are limited to Linux and macOS devices. In addition to being accessible as a mounted drive, SMB file shares can be synchronized between Azure Files and a local share on a Windows Server device using Azure File Sync. This service allows organizations to cache frequently accessed data on the local file share while leaving the least accessed data in Azure.

Access Tiers

Azure Files offers four storage tiers to meet the performance and price requirements of different workloads:

  • Premium file shares use SSDs for storage, providing high performance and low latency for IO-intensive workloads. This tier is only available in premium storage accounts.
  • Transaction optimized file shares use standard HDDs for storage, enabling transaction-heavy workloads that do not need the low latency that premium file shares provide. This tier is available in standard storage accounts.
  • Hot file shares use standard HDDs for storage and are optimized for general-purpose file-sharing scenarios. This tier is available in standard storage accounts.
  • Cool file shares use standard HDDs for storage and offer cost-efficient storage that is optimized for archive storage scenarios. This tier is available in standard storage accounts.

The premium storage tier is the only tier that users can access via SMB and NFS protocols. Transaction optimized, hot, and cool tiers are only offered in standard storage accounts and do not support the NFS protocol as of this writing.

File shares created on a standard storage account switch between the transaction optimized, hot, and cool tiers without needing to move to a different storage account. Moving from one of the standard storage account tiers to the premium tier will require you to create a new premium storage account and copy the data from the old file share to the new one. The data can be copied from the old share to the new one using the AzCopy utility that is described later in this chapter.

More information about the different storage tiers available for Azure Files can be found at https://docs.microsoft.com/en-us/azure/storage/files/storage-files-planning#storage-tiers.

Access Tiers

Azure Blob Storage is regularly used to store data that is frequently and rarely accessed in the same storage account. In these scenarios it is critical to distinguish data that is actively used and data that is archived. For this reason, Azure Blob Storage offers three access tiers that allow users to store blob data in the most cost-effective manner based on how it is used:

  • Hot tier is an online tier for storing data that is frequently accessed. Data that is configured to use this tier is expected to be read from or written to often. This tier has the highest storage costs but the lowest access latency.
  • Cool tier is an online tier for storing data that is infrequently accessed and should be stored for a minimum of 30 days. Typical use cases for the cool access tier include storing short-term data backups and older datasets that are not frequently accessed but need to be available at a moment’s notice.
  • Archive tier is an offline tier for storing data that is almost never accessed and should be stored for a minimum of 180 days. This tier has the lowest storage costs but the highest access costs. Data stored with this access tier should have flexible latency requirements as retrieval can take several hours. Typical use cases for the archive tier include storing long-term backups, compliance data that needs to be retained for regulatory reasons, and raw datasets that must be retained but are never used once they are processed.