Set Blob Tier
Set Blob Tier operation sets the access tier on a blob. The operation is allowed on a page blob in a premium storage account and on a block blob in a blob storage or general purpose v2 account. A premium page blob's tier (
P60) determines the allowed size, IOPS, and bandwidth of the blob. A block blob's tier determines
Archive storage type. This operation does not update the blob's ETag.
For detailed information about block blob-level tiering, see Hot, cool, and archive storage tiers.
You can construct the
Set Blob Tier request as follows. We recommend that you use HTTPS. Replace myaccount with the name of your storage account, and replace myblob with the blob name for which the tier is to be changed.
|Method||Request URI||HTTP version|
You can specify the following additional parameters on the request URI:
||Optional. The snapshot parameter is an opaque
||Optional for version 2019-12-12 and later. The
The required and optional request headers are described in the following table:
||Required. Specifies the authorization scheme, storage account name, and signature. For more information, see Authorize requests to Azure Storage.|
||Required. Specifies the Coordinated Universal Time (UTC) for the request. For more information, see Authorize requests to Azure Storage.|
||Required. Indicates the tier to be set on the blob. For a list of allowed premium page blob tiers, see High-performance Premium Storage and managed disks for VMs. For blob storage or general purpose v2 account, valid values are
||Required for all authorized requests. Specifies the version of the operation to use for this request. For more information, see Versioning for the Azure Storage Services.|
||Optional. Provides a client-generated, opaque value with a 1-kB character limit that is recorded in the analytics logs when storage analytics logging is enabled. Using this header is highly recommended for correlating client-side activities with requests received by the server. For more information, see About Storage Analytics Logging.|
||Optional. Indicates the priority with which to rehydrate an archived blob. Supported on version 2019-02-02 and newer for block blobs. Valid values are
Beginning with version 2020-06-12, the rehydration priority can be updated after it was previously set. The priority setting can be changed from
This operation also supports the use of conditional headers to tier the blob only if a specified condition is met. For more information, see Specify conditional headers for Blob Storage operations.
The response includes an HTTP status code and a set of response headers.
A successful operation returns status code 200 (OK) if the new tier takes effect immediately, or status code 202 (Accepted) if the transition to the new tier is pending.
For premium storage accounts, the page blob operation returns status code 200 (OK).
For block blobs, the HTTP status codes that are returned, based on the current and requested tiers of the blob, are described in the following table:
|Tier||Set to hot tier||Set to cool tier||Set to cold tier||Set to archive tier|
|Blob in hot tier||200||200||200||200|
|Blob in cool tier||200||200||200||200|
|Blob in cold tier||200||200||200||200|
|Blob in archive tier||202||202||202||200|
|Blob in archive tier, rehydrating to hot||202||409||409||409|
|Blob in archive tier, rehydrating to cool||409||202||409||409|
|Blob in archive tier, rehydrating to cold||409||409||202||409|
For more information about status codes, see Status and error codes.
The response for this operation includes the following headers. The response may also include additional standard HTTP headers. All standard headers conform to the HTTP/1.1 protocol specification.
||Uniquely identifies the request that was made and can be used to troubleshoot the request. For more information, see Troubleshoot API operations.|
||The Blob Storage version that was used to execute the request. This header is returned for requests made against version 2009-09-19 and later.|
||Can be used to troubleshoot requests and corresponding responses. The value of this header is equal to the value of the
Authorization is required when calling any data access operation in Azure Storage. You can authorize the
Set Blob Tier operation as described below.
Azure Storage supports using Microsoft Entra ID to authorize requests to blob data. With Microsoft Entra ID, you can use Azure role-based access control (Azure RBAC) to grant permissions to a security principal. The security principal may be a user, group, application service principal, or Azure managed identity. The security principal is authenticated by Microsoft Entra ID to return an OAuth 2.0 token. The token can then be used to authorize a request against the Blob service.
To learn more about authorization using Microsoft Entra ID, see Authorize access to blobs using Microsoft Entra ID.
Listed below are the RBAC action necessary for a Microsoft Entra user, group, or service principal to call the
Set Blob Tier operation, and the least privileged built-in Azure RBAC role that includes this action:
- Azure RBAC action: Microsoft.Storage/storageAccounts/blobServices/containers/blobs/write
- Least privileged built-in role: Storage Blob Data Contributor
To learn more about assigning roles using Azure RBAC, see Assign an Azure role for access to blob data.
Setting a blob's tier for page blobs in premium accounts has the following restrictions:
- The new blob tier can't be lower than the existing one.
- The new blob tier should be able to accommodate the blob's content length. For a list of tiers and their allowed content length, see High-performance premium storage and managed disks for VMs.
Setting the block blob's tier on a Blob Storage or general purpose v2 account has the following restrictions:
- Setting a tier on a snapshot is allowed as of REST version 2019-12-12.
- Snapshots that are tiered to
archivecan't be rehydrated back into the snapshot. That is, the snapshot can't be brought back to a
cooltier. The only way to retrieve the data from an
archivesnapshot or version is to copy it to a new blob.
- If the version is a root blob, it can be rehydrated back to
- Snapshots or versions in an
archivestate aren't allowed to be promoted to root.
- When versioning is enabled, the deletion of a root blob when it's in a rehydrate-pending state will result in the cancellation of the rehydration, and the version will be in an
- If a blob is overwritten when it's in a rehydrate-pending and soft-deleted state, it will result in the cancellation of the rehydration, and the version of the soft-deleted snapshot will be in an
The list of supported tiers is not restricted by the request version, and new tiers may be added in the future.
For detailed information about block blob level tiering see Hot, cool, and archive storage tiers.
Pricing requests can originate from clients that use Blob Storage APIs, either directly through the Blob Storage REST API, or from an Azure Storage client library. These requests accrue charges per transaction. The type of transaction affects how the account is charged. For example, read transactions accrue to a different billing category than write transactions. The following table shows the billing category for
Set Blob Tier requests based on the storage account type:
|Operation||Storage account type||Billing category|
|Set Blob Tier (tier down)||Premium block blob
Standard general-purpose v2
Standard general-purpose v1
|Set Blob Tier (tier up)||Premium block blob
Standard general-purpose v2
Standard general-purpose v1
To learn about pricing for the specified billing category, see Azure Blob Storage Pricing.