doc(backup): related custom resources might disappear

ref: longhorn/longhorn 9530

Signed-off-by: James Lu <[email protected]>

content/docs/1.6.4/deploy/important-notes/index.md

@@ -18,6 +18,7 @@ Please see [here](https://github.com/longhorn/longhorn/releases/tag/v{{< current
   - [Danger Zone Setting Configuration](#danger-zone-setting-configuration)
   - [Longhorn PVC with Block Volume Mode](#longhorn-pvc-with-block-volume-mode)
   - [Minimum XFS Filesystem Size](#minimum-xfs-filesystem-size)
+  - [Backup Related Custom Resources Might Disappear](#backup-related-custom-resources-might-disappear)
 - [V2 Data Engine](#v2-data-engine)
   - [Longhorn System Upgrade](#longhorn-system-upgrade)
   - [Changing Default Huge Page Size to 2 GiB](#changing-default-huge-page-size-to-2-gib)
@@ -223,6 +224,16 @@ Longhorn v{{< current-version >}} does not allow the following:
 However, Longhorn still allows the listed actions when cloning or restoring volumes created with earlier Longhorn
 versions.
 
+### Backup Related Custom Resources Might Disappear
+
+Longhorn will attempt to clean up the backup-related custom resources in the following scenarios:
+
+- An empty response from the NFS server due to a brief server downtime.
+- A race condition between related Longhorn backup controllers.
+
+The backup information will be resynchronized during the next polling interval.  
+For more information, see [#9530](https://github.com/longhorn/longhorn/issues/9530).
+
 ## V2 Data Engine
 
 ### Longhorn System Upgrade

content/docs/1.6.4/snapshots-and-backups/backup-and-restore/set-backup-target.md

@@ -13,6 +13,14 @@ If you don't have access to AWS S3 or want to give the backupstore a try first,
 
 Longhorn also supports setting up recurring snapshot/backup jobs for volumes, via Longhorn UI or Kubernetes Storage Class. See [here](../../scheduling-backups-and-snapshots) for details.
 
+> Note:  
+> Longhorn will attempt to clean up the backup-related custom resources in the following scenarios:
+>
+> - An empty response from the NFS server due to a brief server downtime.
+> - A race condition between related Longhorn backup controllers.
+>
+> The backup information will be resynchronized during the next polling interval. For more information, see [#9530](https://github.com/longhorn/longhorn/issues/9530).
+
 This page covers the following topics:
 
 - [Set up AWS S3 Backupstore](#set-up-aws-s3-backupstore)
@@ -452,5 +460,4 @@ Then, navigate to Longhorn UI > Setting > General > Backup
     azblob-secret
     ```
 
-
 After configuring the above settings, you can manage backups on Azure Blob storage. See [how to create backup](../create-a-backup) for details.

content/docs/1.7.2/important-notes/_index.md

@@ -27,6 +27,8 @@ Please see [here](https://github.com/longhorn/longhorn/releases/tag/v{{< current
   - [Auto-Balance Pressured Disks](#auto-balance-pressured-disks)
 - [Networking](#networking)
   - [Storage Network Support for Read-Write-Many (RWX) Volumes](#storage-network-support-for-read-write-many-rwx-volumes)
+- [Backup](#backup)
+  - [Related Custom Resources Might Disappear](#related-custom-resources-might-disappear)
 - [V2 Data Engine](#v2-data-engine)
   - [Longhorn System Upgrade](#longhorn-system-upgrade)
   - [Enable Both `vfio_pci` and `uio_pci_generic` Kernel Modules](#enable-both-vfio_pci-and-uio_pci_generic-kernel-modules)
@@ -204,6 +206,18 @@ To apply the storage network to existing RWX volumes, you must detach the volume
 
 For more information, see [Issue #8184](https://github.com/longhorn/longhorn/issues/8184).
 
+## Backup
+
+### Related Custom Resources Might Disappear
+
+Longhorn will attempt to clean up the backup-related custom resources in the following scenarios:
+
+- An empty response from the NFS server due to a brief server downtime.
+- A race condition between related Longhorn backup controllers.
+
+The backup information will be resynchronized during the next polling interval.  
+For more information, see [#9530](https://github.com/longhorn/longhorn/issues/9530).
+
 ## V2 Data Engine
 
 ### Longhorn System Upgrade

content/docs/1.7.2/snapshots-and-backups/backup-and-restore/set-backup-target.md

@@ -13,6 +13,14 @@ If you don't have access to AWS S3 or want to give the backupstore a try first,
 
 Longhorn also supports setting up recurring snapshot/backup jobs for volumes, via Longhorn UI or Kubernetes Storage Class. See [here](../../scheduling-backups-and-snapshots) for details.
 
+> Note:  
+> Longhorn will attempt to clean up the backup-related custom resources in the following scenarios:
+>
+> - An empty response from the NFS server due to a brief server downtime.
+> - A race condition between related Longhorn backup controllers.
+>
+> The backup information will be resynchronized during the next polling interval. For more information, see [#9530](https://github.com/longhorn/longhorn/issues/9530).
+
 This page covers the following topics:
 
 - [Set up AWS S3 Backupstore](#set-up-aws-s3-backupstore)
@@ -452,5 +460,4 @@ Then, navigate to Longhorn UI > Setting > General > Backup
     azblob-secret
     ```
 
-
 After configuring the above settings, you can manage backups on Azure Blob storage. See [how to create backup](../create-a-backup) for details.

content/docs/1.8.0/important-notes/_index.md

@@ -28,6 +28,8 @@ Please see [here](https://github.com/longhorn/longhorn/releases/tag/v{{< current
   - [Storage Network Support for Read-Write-Many (RWX) Volumes](#storage-network-support-for-read-write-many-rwx-volumes)
 - [OS Distro Specific](#os-distro-specific)
   - [V2 Data Engine Support for Talos Linux](#talos-linux)
+- [Backup](#backup)
+  - [Related Custom Resources Might Disappear](#related-custom-resources-might-disappear)
 - [V2 Data Engine](#v2-data-engine)
   - [Longhorn System Upgrade](#longhorn-system-upgrade)
   - [Enable Both `vfio_pci` and `uio_pci_generic` Kernel Modules](#enable-both-vfio_pci-and-uio_pci_generic-kernel-modules)
@@ -208,6 +210,18 @@ For more information, see [Issue #8184](https://github.com/longhorn/longhorn/iss
 
 Longhorn v1.8.0 and later versions support usage of V2 volumes in Talos Linux clusters. To use V2 volumes, ensure that all nodes meet the V2 Data Engine prerequisites. For more information, see [Talos Linux Support: V2 Data Engine](../advanced-resources/os-distro-specific/talos-linux-support#v2-data-engine).
 
+## Backup
+
+### Related Custom Resources Might Disappear
+
+Longhorn will attempt to clean up the backup-related custom resources in the following scenarios:
+
+- An empty response from the NFS server due to a brief server downtime.
+- A race condition between related Longhorn backup controllers.
+
+The backup information will be resynchronized during the next polling interval.  
+For more information, see [#9530](https://github.com/longhorn/longhorn/issues/9530).
+
 ## V2 Data Engine
 
 ### Longhorn System Upgrade

content/docs/1.8.0/snapshots-and-backups/backup-and-restore/set-backup-target.md

@@ -13,6 +13,14 @@ If you don't have access to AWS S3 or want to give the backupstore a try first,
 
 Longhorn also supports setting up recurring snapshot/backup jobs for volumes, via Longhorn UI or Kubernetes Storage Class. See [here](../../scheduling-backups-and-snapshots) for details.
 
+> Note:  
+> Longhorn will attempt to clean up the backup-related custom resources in the following scenarios:
+>
+> - An empty response from the NFS server due to a brief server downtime.
+> - A race condition between related Longhorn backup controllers.
+>
+> The backup information will be resynchronized during the next polling interval. For more information, see [#9530](https://github.com/longhorn/longhorn/issues/9530).
+
 This page covers the following topics:
 
 - [Set up AWS S3 Backupstore](#set-up-aws-s3-backupstore)
@@ -452,5 +460,4 @@ Then, navigate to Longhorn UI > Setting > General > Backup
     azblob-secret
     ```
 
-
 After configuring the above settings, you can manage backups on Azure Blob storage. See [how to create backup](../create-a-backup) for details.