Merge pull request #313588 from codefinite-vri/main

Robocopy note updates regarding output

Author: prmerger-automator[bot]

articles/storage/file-sync/file-sync-monitoring.md

@@ -98,14 +98,14 @@ The following metric charts are viewable in the Storage Sync Service portal:
 | Agent Version Expiration Information | Number of days until the agent version expires | Storage Sync Service - Metrics |
 | Bytes synced | Size of data transferred (upload and download) | Sync Group - Status, Server endpoint - Sync status, Storage Sync Service - Metrics |
 | Cache data size by last access time | Size of data by last access time | Server Endpoint - Cloud Tiering Status, Storage Sync Service - Metrics |
-| Cloud tiering cache hit rate | Percentage of bytes that have been served from the cache vs. recalled from the cloud | Sync Group - Status, Server Endpoint - Cloud Tiering Status, Storage Sync Service - Metrics |
+| Cloud tiering cache hit rate | Percentage of bytes that have been served from the cache vs. recalled from the cloud. This metric is generated only when there is active I/O (such as file reads or recalls) on the server endpoint. | Sync Group - Status, Server Endpoint - Cloud Tiering Status, Storage Sync Service - Metrics |
 | Cloud tiering low disk space mode | Status of disk space on server | Storage Sync Service - Metrics |
-| Cloud tiering recall success rate | Success status of cloud tiering recall | Storage Sync Service - Metrics |
+| Cloud tiering recall success rate | Success status of cloud tiering recall. This metric is generated only when there is active I/O (such as file reads or recalls) on the server endpoint. | Storage Sync Service - Metrics |
 | Cloud tiering size of data tiered | Size of data tiered | Storage Sync Service - Metrics |
 | Cloud tiering size of data tiered by last maintenance job | Size of data tiered during last maintenance job. | Storage Sync Service - Metrics |
 | Cloud tiering recall size | Size of data recalled | Sync Group – Status, Registered Servers, Storage Sync Service - Metrics |
-| Cloud tiering recall size by application | Size of data recalled by application | Server Endpoint - Cloud Tiering Status, Storage Sync Service - Metrics |  
-| Cloud tiering recall throughput | Throughput of data recalled | Storage Sync Service - Metrics |
+| Cloud tiering recall size by application | Size of data recalled by application. This metric is generated only when there is active I/O (such as file reads or recalls) on the server endpoint. | Server Endpoint - Cloud Tiering Status, Storage Sync Service - Metrics |  
+| Cloud tiering recall throughput | Throughput of data recalled. This metric is generated only when there is active I/O (such as file reads or recalls) on the server endpoint. | Storage Sync Service - Metrics |
 | Egress Breakdown | Egress breakdown by user recalls of tiered files, background recalls, and sync downloads | Server Endpoint - Cloud Tiering Status |
 | Files synced | Count of files transferred (upload and download) | Sync Group - Status, Server endpoint - Sync status, Storage Sync Service - Metrics |
 | Files not syncing | Count of files that are failing to sync | Sync Group - Status, Server endpoint - Sync status, Storage Sync Service - Metrics |

articles/storage/files/storage-files-migration-nas-hybrid-databox.md

@@ -183,6 +183,12 @@ The following Robocopy command will copy only the differences (updated files and
 
 [!INCLUDE [storage-files-migration-robocopy](../../../includes/storage-files-migration-robocopy.md)]
 
+RoboCopy might report that files were copied even when no data transfer was necessary. This behavior occurs because robocopy evaluates both file data and metadata changes when producing its output. To correctly interpret the results, review the file status in the command output:
+- Newer: File data is copied to the destination.
+- Modified: Only metadata is updated; file data isn't recopied.
+
+In both cases, RoboCopy might report byte counts as though data was transferred. This behavior can lead to confusion when validating copy operations.
+
 If you provisioned less storage on your Windows Server instance than your files use on the NAS appliance, you've configured cloud tiering. As the local Windows Server volume becomes full, [cloud tiering](../file-sync/file-sync-cloud-tiering-overview.md) will kick in and tier files that have already successfully synced. Cloud tiering will generate enough space to continue the copy from the NAS appliance. Cloud tiering checks once an hour to determine what has synced and to free up disk space to reach the 99 percent volume free space.
 
 Robocopy might need to move more files than you can store locally on the Windows Server instance. You can expect Robocopy to move faster than Azure File Sync can upload your files and tier them off your local volume. In this situation, Robocopy will fail. We recommend that you work through the shares in a sequence that prevents this scenario. For example, move only shares that fit in the free space available on the Windows Server instance. Or avoid starting Robocopy jobs for all shares at the same time. The good news is that the `/MIR` switch will ensure that only deltas are moved. After a delta has been moved, a restarted job won't need to move the file again.

articles/storage/files/storage-files-migration-robocopy.md

@@ -69,6 +69,14 @@ robocopy <SourcePath> <Dest.Path> /MT:20 /R:2 /W:1 /B /MIR /IT /COPY:DATSO /DCOP
 | `/Z`                  | **Use cautiously** </br>Copies files in restart mode. This switch is recommended only in an unstable network environment. It significantly reduces copy performance because of extra logging. |
 | `/ZB`                 | **Use cautiously** </br>Uses restart mode. If access is denied, this option uses backup mode. This option significantly reduces copy performance because of checkpointing. |
 
+RoboCopy might report that files were copied even when no data transfer was necessary. This behavior occurs because robocopy evaluates both file data and metadata changes when producing its output.
+
+To correctly interpret the results, review the file status in the command output:
+- Newer: File data is copied to the destination.
+- Modified: Only metadata is updated; file data isn't recopied.
+
+In both cases, RoboCopy might report byte counts as though data was transferred. This behavior can lead to confusion when validating copy operations.
+
 > [!IMPORTANT]
 > We recommend using a Windows Server 2022 or newer. When using a Windows Server 2019, ensure at the latest patch level or at least [OS update KB5005103](https://support.microsoft.com/topic/august-26-2021-kb5005103-os-build-18363-1766-preview-4e23362c-5e43-4d8f-95e5-9fdade60605f) is installed. It contains important fixes for certain Robocopy scenarios.
 

includes/storage-files-migration-robocopy.md

@@ -36,3 +36,9 @@ robocopy <SourcePath> <Dest.Path> /MT:20 /R:2 /W:1 /B /MIR /IT /COPY:DATSO /DCOP
 
 > [!IMPORTANT]
 > We recommend using a Windows Server 2022. When using a Windows Server 2019, ensure at the latest patch level or at least [OS update KB5005103](https://support.microsoft.com/topic/august-26-2021-kb5005103-os-build-18363-1766-preview-4e23362c-5e43-4d8f-95e5-9fdade60605f) is installed. It contains important fixes for certain Robocopy scenarios.
+
+RoboCopy might report that files were copied even when no data transfer was necessary. This behavior occurs because robocopy evaluates both file data and metadata changes when producing its output. To correctly interpret the results, review the file status in the command output:
+- Newer: File data is copied to the destination.
+- Modified: Only metadata is updated; file data isn't recopied.
+
+In both cases, RoboCopy might report byte counts as though data was transferred. This behavior can lead to confusion when validating copy operations.