Merge pull request #287864 from b-ahibbard/cool-tiering

cool tiering policy

Author: prmerger-automator[bot]

articles/azure-netapp-files/cool-access-introduction.md

@@ -5,7 +5,7 @@ services: azure-netapp-files
 author: b-ahibbard
 ms.service: azure-netapp-files
 ms.topic: how-to
-ms.date: 03/03/2025
+ms.date: 03/06/2025
 ms.author: anfdocs
 ms.custom: references_regions
 ---
@@ -135,6 +135,12 @@ When you create volumes in the capacity pool and start tiering data to the cool
     * 0.75-TiB capacity at the cool tier rate.
     * Network transfer between the hot tier and the cool tier. The markup on top of the transaction cost (`GET`, `PUT`) on blob storage and private link transfer in either direction between the hot tiers determines the rate.
 
+* Azure NetApp Files storage with cool access also enables you to only tier snapshots. For this scenario, assume you create one 1-TiB volume where 10% of the volume data is snapshots and enable cool access with the `-snapshots-only` policy. The billing calculation is: 
+
+    * 0.9-TiB capacity at the hot tier
+    * 0.1-TiB capacity at the cool tier
+    * Data transfers costs occur for the initial transfer of snapshots, then network transfer costs incur only when snapshots are restored. 
+
 ### Examples of cost calculations with varying coolness periods
 
 This section shows you examples of storage and network transfer costs with varying coolness periods.
@@ -263,6 +269,8 @@ Your first 12-month savings:
 * Cost with cool access: First month + Second month + … + twelfth month = (2 x $755.00) + $586.52 + (9 x $498.18) = $6,580.14
 * Savings using cool access: **27.37%**
 
+#### Example 4: 
+
 > [!TIP]
 > You can use the [Azure NetApp Files storage with cool access cost savings estimator](https://aka.ms/anfcoolaccesscalc) to interactively estimate cost savings based on changeable input parameters.
 

articles/azure-netapp-files/manage-cool-access.md

@@ -5,7 +5,7 @@ services: azure-netapp-files
 author: b-ahibbard
 ms.service: azure-netapp-files
 ms.topic: how-to
-ms.date: 03/03/2025
+ms.date: 03/06/2025
 ms.author: anfdocs
 ---
 
@@ -25,6 +25,7 @@ There are several considerations to be aware of when using cool access.
 
 * No guarantee is provided for any maximum latency for client workload for any of the service tiers.
 * Although cool access is available for the Standard, Premium, and Ultra service levels, how you're billed for using the feature differs from the hot tier service-level charges. For details and examples, see the [Billing section](cool-access-introduction.md#billing).
+* Cool access supports two tiering policies: `Auto` and `SnapshotOnly`. The `SnapshotOnly` policy limits data tiering to data in snapshots, while all data blocks associated with files in the active file system remain in the hot tier. The `Auto` policy encompasses both snapshot copy data and data in the active file system.
 * You can convert an existing capacity pool into a cool-access capacity pool to create cool access volumes. After the capacity pool is enabled for cool access, you can't convert it back to a non-cool-access capacity pool.  
     * When you enable cool access, data that satisfies the conditions set by the coolness period moves to the cool tier. For example, if the coolness period is set to 30 days, any data that has been cool for at least 30 days moves to the cool tier _when_ you enable cool access. Once the coolness period is reached, background jobs can take up to 48 hours to initiate the data transfer to the cool tier. 
 * A cool-access capacity pool can contain both volumes with cool access enabled and volumes with cool access disabled.
@@ -46,14 +47,14 @@ There are several considerations to be aware of when using cool access.
 
 - When a volume containing data in the cool tier is deleted, the deletion process occurs directly from the cool tier without rehydrating the data to the hot tier. The data marked for deletion is cleaned up according to the job scheduled in the service.  
 
-    Once the volume is deleted in Azure NetApp Files, the data in the associated Azure Blob storage is marked for deletion. Although the data remains in Azure Blob storage until the cleanup job finishes, you aren't charged for the deleted volume. The service manages billing details. After the volume is deleted, you don't incur costs for the data pending deletion in Azure storage.  
+    When the volume is deleted in Azure NetApp Files, the data in the associated Azure Blob storage is marked for deletion. Although the data remains in Azure Blob storage until the cleanup job finishes, you aren't charged for the deleted volume. The service manages billing details. After the volume is deleted, you don't incur costs for the data pending deletion in Azure storage.  
 
 - **Data rehydration:** Data isn't rehydrated to the hot tier when the volume is deleted, ensuring the deletion process is efficient and mitigating unnecessary data movement. 
     - The only way to rehydrate data from the cool tier to the hot tier is for the client or application to read the data block. 
 
 ### Considerations for moving volumes to another capacity pool
 
-* Volumes enabled for cool access can be moved between capacity pools only if those capacity pools are enabled for cool access. Once a volume has been enabled for cool access, it can only reside in a cool access-enabled capacity pool even if cool access has been disabled on the volume. 
+* Volumes enabled for cool access can be moved between capacity pools only if those capacity pools are enabled for cool access. When a volume is enabled for cool access, it can only reside in a cool access-enabled capacity pool even if cool access has been disabled on the volume. 
 * If you [move a cool access volume to another capacity pool (service level change)](dynamic-change-volume-service-level.md), you must also enable that pool for cool access.
 * If you disable cool access and turn off tiering on a cool access volume (that is, the volume no longer uses cool access), you can't move it to a non-cool-access capacity pool. In a cool access capacity pool, you can move all volumes, *whether they're enabled for cool access or not*, only to another cool access capacity pool.  
 
@@ -141,11 +142,14 @@ You can enable Azure NetApp Files storage with cool access during the creation o
             * If **Cool Access Retrieval Policy** is set to **Never**: Cold data is served directly from the cool tier and isn't retrieved to the hot tier.
         * Cool access is **disabled**:
             * You can set a cool access retrieval policy if cool access is disabled only if there's existing data on the cool tier. 
-            * Once you disable the cool access setting on the volume, the cool access retrieval policy remains the same.    
+            * After you disable the cool access setting on the volume, the cool access retrieval policy remains the same.    
 
     * **Cool Access Tiering Policy** 
 
-        Select `Auto`. The `SnapshotOnly` policy is not currently supported. 
+        Select either `SnapshotOnly` or `Auto`. 
+
+        * The `SnapshotOnly` policy limits data tiering to data in snapshots, while all data blocks associated with files in the active file system remain in the hot tier.
+        * The `Auto` policy encompasses both snapshot copy data and data in the active file system. 
 
     :::image type="content" source="./media/manage-cool-access/cool-access-new-volume.png" alt-text="Screenshot that shows the Create a volume page. On the Basics tab, the Enable Cool Access checkbox is selected. The options for the cool access retrieval policy are displayed. " lightbox="./media/manage-cool-access/cool-access-new-volume.png"::: 
 

articles/azure-netapp-files/whats-new.md

@@ -6,7 +6,7 @@ author: b-hchen
 ms.service: azure-netapp-files
 ms.custom: linux-related-content
 ms.topic: overview
-ms.date: 03/04/2025
+ms.date: 03/06/2025
 ms.author: anfdocs
 ---
 
@@ -16,6 +16,10 @@ Azure NetApp Files is updated regularly. This article provides a summary about t
 
 ## March 2025
 
+* [Storage with cool access enhancement:](manage-cool-access.md) snapshot-only tiering policy
+
+    Azure NetApp Files storage with cool access now supports a snapshots-only policy. With this policy enabled, only snapshots are moved to the cool tier. 
+
 * [Edit network features enhancement: no downtime](configure-network-features.md#no-downtime) is now generally available (GA)
 
     Azure NetApp Files now supports the ability to edit network features (that is, upgrade from Basic to Standard network features) with no downtime for Azure NetApp Files volumes. Standard Network Features provide you with an enhanced virtual networking experience for a seamless and consistent experience along with security posture for Azure NetApp Files. This feature is available in all Azure NetApp Files regions.