Troubleshoot backup failures

Unified diagnostic framework

Follow these steps to diagnose backup failures for any data source:

1. Verify client status, network connectivity, and permissions

2. Validate data source availability and configuration

3. Check API calls, backend task status, and system health

4. Analyze logs, identify performance bottlenecks, and investigate edge cases

This framework applies to all data sources below.

Step 1: Determine whether a client is required

• Data sources that do not require client installation

  When you back up Alibaba Cloud storage resources, such as OSS objects, NAS file systems, Tablestore instances, and ECS instances, in the Cloud Backup console for the first time, Cloud Backup uses the related service-linked roles to read these resources without installing a client. For more information about how to resolve backup failures and timeout errors in this scenario, see Step 2: Resolve failures without a client installed.

• Data sources requiring client installation

  When you back up files, on-premises server files, ECS instances, on-premises databases (MySQL, Oracle, and SQL Server), VMs, and large-scale NAS file systems that are stored in self-managed data centers, you must install a Cloud Backup client. Cloud Backup clients support Windows and Linux operating systems. For more information about how to resolve backup failures and timeout errors in this scenario, see Step 3: Resolve backup failures when a Cloud Backup client is installed.

Learn about the product in What is Cloud Backup? and Features supported by Cloud Backup.

Step 2: Resolve failures without a client installed

1. In the Cloud Backup console, modify and confirm the configurations as prompted.

2. Troubleshoot a job that fails to back up OSS objects.

   • Status of the Backup Jobs: Failed (The OSS bucket does not exist.)

     The OSS bucket has been deleted.

     • If the deletion was intentional, ignore the job status. To avoid unnecessary storage fees, click Storage Vaults in the left navigation pane and delete the storage vault.

     • If the deletion was unintentional, create a new OSS bucket in the same region and restore objects to it. Create an OSS restore job.

3. Troubleshoot a job that fails to back up a NAS file system.

   If Status of the backup job is abnormal, check the following:

   • Status of the Backup Jobs: Failed (The path cannot be accessed.)

     The path specified in Source Paths does not exist. Update the source path to a valid network path. On the Backup Plans tab, find the file system and choose <hd> More </hd> > Modify Plan in the Actions column.

   • Status of the Backup Jobs: Failed (The specified file system does not exist.)

     The NAS file system has been deleted.

     • If the deletion was intentional, ignore the job status. To avoid unnecessary storage fees, click Storage Vaults in the left navigation pane and delete the storage vault.

     • If the deletion was unintentional, create a NAS file system in the same region and restore files to it. Create a NAS restore job.

   • Status of the Backup Jobs: Failed (The mounting fails.)

     1. On the Backup Plans tab, access the NAS file system on the Alibaba Cloud NAS tab. Ensure that VPC Default Permission Group (All Allowed) is used by the mount target Cloud Backup created for the NAS file system, and that it allows access from all IP addresses (0.0.0.0/0). If the default permission group restricts access, contact Alibaba Cloud NAS technical support.

        

        

        

     2. Alibaba Cloud NAS does not support the SMB access control list (ACL) feature. If ACL is enabled for your SMB file system, Cloud Backup cannot access it.

4. Troubleshoot a job that fails to back up a Tablestore instance.

   If Status of the backup job is abnormal, check the following:

   • Status of the Backup Jobs: Failed

     Modify and confirm the configurations as prompted.

   • Instance Status of the Tablestore instance: Released

     The Tablestore instance has been deleted.

     • If the deletion was intentional, ignore the job status. To avoid unnecessary storage fees, click Storage Vaults in the left navigation pane and delete the storage vault.

     • If the deletion was unintentional, create a Tablestore instance in the same region and restore tables to it. Restore Tablestore tables.

Step 3: Resolve failures with a client installed

1. In the Cloud Backup console, modify and confirm the configurations as prompted.

2. Check the client status. For more information, see How do I check the status of a Cloud Backup client? and Handle status exceptions on a Cloud Backup client

3. Occasional failures are typically caused by network jitter or temporary disconnections — no action is needed, and the backup resumes automatically. If failures persist, use the diagnostic tool for Cloud Backup clients to monitor the client's network environment. Common network issues.

4. The local NAS mount failed.

   The Cloud Backup client configuration is incorrect, or the required mount tool is not installed.

   Windows client

   On-premises NAS files are shared over a network. To back up or archive these files, select This user. The user must meet these requirements:

   • Has local administrator permissions.

   • Has the "Log on as a service" permission.

     Perform the following steps:

     1. Open the Control Panel. In the window that appears, click Administrative Tools.

     2. Open Local Security Policy and choose Local Policies > User Rights Assignment.

     3. Turn on Log on as a service. In the dialog box that appears, add a user.

   • Has permissions to access network-shared files.

   For more information, see How do I select a component and account when I install a Cloud Backup client?

   Linux client

   The Network File System (NFS) and SMB protocols are supported. You can select a tool based on the protocol of your NAS file system.

   • NFS tool

     • CentOS

       sudo yum install nfs-utils

     • Ubuntu

       sudo apt-get install nfs-common

   • SMB tool

     • Centos

       sudo yum install cifs-utils

     • Ubuntu

       sudo apt-get install cifs-utils

     • openSUSE

       sudo zypper install cifs-utils

5. If an out-of-memory (OOM) error occurs due to insufficient resources:

   1. Scale up resources.

   2. Split the source directory into multiple subdirectories. Method 1: Split the source path.

   3. Enable bandwidth throttling and configure related parameters in the backup plan.

   4. Reduce client resource usage by modifying its configuration file. Method 3: Reduce the resource consumption of the Cloud Backup client.

6. If a timeout occurs, check the hbrclient.log file. If "Program Stopping!" appears, the client was restarted. Log file paths:

   • On Linux: /opt/alibabacloud/hbrclient/logs/hbrclient.log

   • On Windows: C:\Program Files\Aliyun Hybrid Backup Service Client\logs\hbrclient.log

If the issue persists, contact technical support.

Step 4: Online technical support

For additional assistance, contact Online Technical Support. Provide the backup plan ID, region, data source type, and task ID. Describe what you were doing, when the problem occurred, and the expected outcome. Include relevant log files.

References

• How do I check the status of a Cloud Backup client?

• Where are Cloud Backup client logs stored?

• How do I uninstall a Cloud Backup client?

• How do I resolve OOM issues on a Cloud Backup client?

• Handle status exceptions on a Cloud Backup client

• Cloud Backup client diagnostic tool

• How do I select a component and account when I install a Cloud Backup client?