TS updates

Author: AbhishekMallick-MS

articles/backup/azure-kubernetes-service-backup-troubleshoot.md

@@ -2,7 +2,7 @@
 title: Troubleshoot Azure Kubernetes Service backup
 description: Symptoms, causes, and resolutions of the Azure Kubernetes Service backup and restore operations.
 ms.topic: troubleshooting
-ms.date: 12/28/2023
+ms.date: 02/28/2024
 ms.service: backup
 ms.custom:
   - ignite-2023
@@ -222,6 +222,88 @@ This error code can appear while you enable AKS backup to store backups in a vau
 
 3. Create a backup policy for operational tier backup (only snapshots for the AKS cluster).
 
+## AKS backup and restore jobs completed with warnings
+
+### UserErrorPVSnapshotDisallowedByPolicy
+
+**Error code**: UserErrorPVSnapshotDisallowedByPolicy
+
+**Cause**: An Azure policy is assigned over subscription that ceases the CSI driver to take the volume snapshot.
+
+**Recommended action**: Remove the Azure Policy ceasing the disk snapshot operation, and then perform an on-demand backup.
+
+### UserErrorPVSnapshotLimitReached
+
+**Error code**: UserErrorPVSnapshotLimitReached
+
+**Cause**: There is a limited number of snapshots for a Persistent Volume that can exist at a point-in-time. For Azure Disk-based Persistent Volumes, the limit is *500 snapshots*. This error appears when snapshots for specific Persistent Volumes aren't taken due to existence of snapshots higher than the supported limits.
+
+**Recommended action**: Update the Backup Policy to reduce the retention duration and wait for older recovery points to be deleted by the Backup vault.
+
+### CSISnapshottingTimedOut
+
+**Error code**: CSISnapshottingTimedOut
+
+**Cause**: Snapshot has failed because CSI Driver is getting timed out to fetch the snapshot handle.  
+
+**Recommended action**: Review the logs and retry the operation to get successful snapshots by running an on-demand backup, or wait for next scheduled backup.
+
+### UserErrorHookExecutionFailed
+
+**Error code**: UserErrorHookExecutionFailed
+
+**Cause**: When hooks applied to run along with backups and restores have encountered an error, and aren't successfully applied.
+
+**Recommended action**: Review the logs, update the hooks, and then retry backup/restore operation.
+
+### UserErrorNamespaceNotFound
+
+**Error code**: UserErrorNamespaceNotFound
+
+**Cause**: Namespaces provided in Backup Configuration is missing while performing backups. Either the namespace was wrongly provided or has been deleted.
+
+**Recommended action**: Check if the Namespaces to be backed up are correctly provided.
+
+### UserErrorPVCHasNoVolume
+
+**Error code**: UserErrorPVCHasNoVolume
+
+**Cause**: The Persistent Volume Claim (PVC) in context does not have a Persistent Volume attached to it. So, the PVC will not be backed up.
+
+**Recommended action**: Attach a volume to the PVC, if it needs to be backed up.
+
+### UserErrorPVCNotBoundToVolume
+
+**Error code**: UserErrorPVCNotBoundToVolume
+
+**Cause**: The PVC in context is in *Pending* state and doesn't have a Persistent Volume attached to it. So, the PVC will not be backed up. 
+
+**Recommended action**: Attach a volume to the PVC, if it needs to be backed up.
+
+### UserErrorPVNotFound
+
+**Error code**: UserErrorPVNotFound
+
+**Cause**: The underlying storage medium for the Persistent Volume is missing. 
+
+**Recommended action**: Check and attached a new Persistent Volume with actual storage medium attached.
+
+### UserErrorStorageClassMissingForPVC
+
+**Error code**: UserErrorStorageClassMissingForPVC
+
+**Cause**: AKS backup checks for the storage class being used and skips the Persistent Volume from taking snapshots due to unavailability of the class. 
+
+**Recommended action**: Update the PVC specifications with the storage class used.
+
+### UserErrorSourceandTargetClusterCRDVersionMismatch
+
+**Error code**: UserErrorSourceandTargetClusterCRDVersionMismatch
+
+**Cause**: The source AKS cluster and Target AKS cluster during restore have different versions of *FlowSchema* and *PriorityLevelConfigurations CRs*. Some Kubernetes resources aren't restored due to the mismatch in cluster versions.
+
+**Recommended action**: Use same cluster version for Target cluster as Source cluster or manually apply the CRs.
+
 ## Next steps
 
 - [About Azure Kubernetes Service (AKS) backup](azure-kubernetes-service-backup-overview.md)

articles/backup/azure-kubernetes-service-cluster-manage-backups.md

@@ -153,7 +153,7 @@ To view these warnings, select **View Details** next to **Warning Details**.
 
 :::image type="content" source="./media/azure-kubernetes-service-cluster-manage-backups/example-backup-job-with-warning-details.png" alt-text="Screenshot shows the job warming details." lightbox="./media/azure-kubernetes-service-cluster-manage-backups/example-backup-job-with-warning-details.png"::: 
 
-Learn [how to identify and resolve the error](). 
+Learn [how to identify and resolve the error](azure-kubernetes-service-backup-troubleshoot.md#aks-backup-extension-installation-error-resolutions). 
 
 ## Next steps