Troubleshooting in Cloud Backup

This section describes typical problems you may encounter while using Cloud Backup and gives troubleshooting recommendations.

• Why cannot I add a VM or BareMetal server to Cloud Backup?

• How do I reconnect a VM or BareMetal server deleted from Cloud Backup?

• How do I reconnect a VM or BareMetal server to Cloud Backup after recovering its backup to another VM or server?

• Why are old backups not deleted after reconnecting a VM to Cloud Backup?

• Error when trying to recover a VM or BareMetal server from a backup

• Error when connecting to a Windows VM

• Authorization error when installing a Cloud Backup agent on a Linux VM

• How do I update the Cloud Backup agent on a VM?

• Why are backups disabled after the OS update?

• Why does it take so long to create a backup?

• Creating incremental backups of a VM or BareMetal server is taking longer than usual

• Out-Of-Memory Killer (OOM Killer) kills the Cloud Backup agent process in Linux

• How do I restore a VM or BareMetal server with LVM from a backup?

• Issues installing the Cloud Backup agent on a VM with low computing resources

• Why does the console give Cloud Backup backup sizes not matching the actual backup sizes?

• If I delete a VM, will its backups remain?

• Code 400 error when installing the agent

• How do I view Cloud Backup activity logs?

• Unable to install agent error during installation

• Cloud Backup VM stuck in the Registering status for a long time

Why cannot I add a VM or BareMetal server to Cloud Backup?Why cannot I add a VM or BareMetal server to Cloud Backup?

Make sure that:

How do I reconnect a VM or BareMetal server deleted from Cloud Backup?How do I reconnect a VM or BareMetal server deleted from Cloud Backup?

If you have deleted a VM or BareMetal server from Cloud Backup and want to reconnect it to the service, follow these guides:

How do I reconnect a VM or BareMetal server to Cloud Backup after restoring its backup to another VM or server?How do I reconnect a VM or BareMetal server to Cloud Backup after restoring its backup to another VM or server?

Why are old backups not deleted after reconnecting a VM to Cloud Backup?Why are old backups not deleted after reconnecting a VM to Cloud Backup?

When reconnecting, the VM is added to Cloud Backup as a new resource. Backups of the new VM are stored as per the linked backup policy.

The backup policy rules do not apply to the old VM's backups. Their storage is subject to the pricing policy. If you do not need those backups, delete them manually or use bulk delete.

I get an error when trying to restore a VM or BareMetal server from a backupI get an error when trying to restore a VM or BareMetal server from a backup

Error message:

Not all of the items are mapped. Please, check your goal instance and its volumes.

The error occurs because Cloud Backup cannot find a suitably sized disk on the target VM.

The boot disk of the target VM or BareMetal server must be at least the size of that of the source VM.

Check the target VM disks and increase their size if needed. You can also use another VM or BareMetal server with suitable parameters.

Error when connecting to a Windows VMError when connecting to a Windows VM

Error message:

Fetching agent id from config
Iteration 0: The term 'acropsh' is not recognized as the name of a cmdlet, function, script file, or operable program. Check the spelling of the name, or if a path was included, verify that the path is correct and try again.

Make sure that:

• Cloud Backup supports the VM operating system.
• The service account linked to the VM has the backup.editor role.
• Network access for your VM is enabled.
• The PowerShell execution policies allow scripts. If not, allow scripts and restart PowerShell. For more information, see this Microsoft guide.

Authorization error when installing a Cloud Backup agent on a Linux VMAuthorization error when installing a Cloud Backup agent on a Linux VM

Error message:

Failed to parse cloudbackup from instance attributes IAM token and instance registration id are empty, unable to provide authorization

The error occurs if the VM has no service account or if the account was configured incorrectly.

Make sure that:

• You have a service account associated with the VM.
• Your service account has the backup.editor role.

How do I update the Cloud Backup agent on a VM?How do I update the Cloud Backup agent on a VM?

Use this guide: Updating the Cloud Backup agent on a VM.

Why are backups disabled after the OS update?Why are backups disabled after the OS update?

Updating the Linux kernel on a resource connected to Cloud Backup may affect the performance of the Cloud Backup agent: it will not be able to create a backup of the resource or recover it from a backup.

This may affect the agent’s performance, since the SnapAPI module (developed by the backup provider for the agent to work with disks and built by the DKMS framework for a specific Linux kernel) may not update after updating the kernel and may therefore cease to match the kernel version.

To restore the Cloud Backup agent’s performance affected by a Linux kernel update, you need to update the version of the Linux kernel headers DKMS refers to when building the SnapAPI module. Once the kernel header version matches the kernel version, DKMS will rebuild the SnapAPI module for the required Linux kernel version at the next start of the resource.

For information on how to upgrade the Linux kernel header version, see Recovering the Cloud Backup agent after a Linux kernel update.

Why does it take so long to create a backup?Why does it take so long to create a backup?

The possible causes may include the following:

• High compression ratio of the backup.

  The backup policy specification describes the following compression levels:

  • COMPRESSION_UNSPECIFIED: Not specified.
  • NORMAL: Standard compression ratio.
  • HIGH: High compression ratio.
  • MAX: Maximum compression ratio.
  • OFF: Disabled.

  As compression ratio increases, the algorithm spends more and more computing resources to find redundancies in data to pack it even denser. Using high compression levels (HIGH, MAX) increases backup generation time.

• Changed Block Tracking not used.

  In Cloud Backup, this logic is set up via the cbt parameter in the backup policy specification. It has several possible values:

  • CHANGED_BLOCK_TRACKING_UNSPECIFIED: Unspecified (default).
  • USE_IF_ENABLED: Use if the feature is enabled.
  • ENABLE_AND_USE: Enable and use explicitly.
  • DO_NOT_USE: Do not use.

  To speed up the backup generation process, we recommend the ENABLE_AND_USE option.

  As such, the cbt setting sets the strategy; the actual tracking of changes on the disk is set up via another parameter: fastBackupEnabled.

• fastBackupEnabled set to false.

  This parameter decides exactly how Cloud Backup will understand that the file has changed.

  • If fastBackupEnabled: true, the changes are detected based on file size and timestamp. This is exactly what fast backup is all about.
  • If fastBackupEnabled: false, Cloud Backup will compare the file's entire content against the backup to figure out the changes.

• Large size of the backed up disk.

Creating incremental backups of a VM or BareMetal server is taking longer than usualCreating incremental backups of a VM or BareMetal server is taking longer than usual

Antivirus activity may affect the time required to create incremental backups under a policy with the fast backup option enabled (fastBackupEnabled). See details in Interaction with an antivirus.

Out-Of-Memory Killer (OOM Killer) kills the Cloud Backup agent process in LinuxOut-Of-Memory Killer (OOM Killer) kills the Cloud Backup agent process in Linux

To speed up data backup and recovery, the Cloud Backup agent tends to consume significant amounts of RAM of the resource it is backing up. The agent can even use up all the available RAM, which in some cases may disrupt the resource's other services and make it impossible to complete the backup or recovery process.

To prevent such issues, limit the amount of data the agent caches in RAM.

How do I restore a VM or BareMetal server with LVM from a backup?How do I restore a VM or BareMetal server with LVM from a backup?

If you are using LVM to manage the disk space of the protected resource, learn how to restore resources with LVM in Cloud Backup.

Issues installing the Cloud Backup agent on a VM with low computing resourcesIssues installing the Cloud Backup agent on a VM with low computing resources

Installing a Cloud Backup agent is a resource-intensive operation. If you want to use a VM in the minimum possible configuration or, for example, a VM with a vCPU performance level below 100%, we recommend increasing the VM's resources during the Cloud Backup agent installation.

Why does the console give Cloud Backup backup sizes not matching the actual backup sizes?Why does the console give Cloud Backup backup sizes not matching the actual backup sizes?

The backup size difference is due to Cloud Backup's internal design: the calculation is based on archives, not the backups themselves.

You can view the size of each archive in the Yandex Cloud CLI using the yc backup backup list-archives command.

If you add up the sizes of each archive, you will get the value you see in the management console.

If I delete a VM, will its backups remain?If I delete a VM, will its backups remain?

Yes. Deleting a VM does not delete its backups. The latter are linked to the backup policy, not the VM.

Code 400 error when installing the agentCode 400 error when installing the agent

Complete error message:

Cloud backup service request for registering agent failed: unexpected status code: url=<https://backup.api.cloud.yandex.net/backup/agent/v1/api/registerAgent>, status=400

The agent may already be linked to another VM created from an image with the agent installed.

To fix the issue, try reconnecting the virtual machine to Cloud Backup.

If reconnection does not help, submit a support ticket.

How do I view Cloud Backup activity logs?How do I view Cloud Backup activity logs?

In Linux kernel-based systems, e.g., Ubuntu, you can find Cloud Backup log files at the following paths:

• /var/log/baas-agent-installer/log.txt
• /var/log/trueimage-setup.log
• /var/log/Acronis

In Windows systems, the Cloud Backup log is in the %AppData%\BackupAgentInstaller*.log file.

You can also generate a local system report:

• Linux: Run a bash script with root privileges to generate a report: /usr/lib/Acronis/BackupAndRecovery/systeminfo.
• Windows: Run C:\Program Files\Common Files\Acronis\AdvReport\systeminfo.exe.

For more on this, see the relevant backup provider guide.

error during installationUnable to install agent error during installation

More often than not, this error occurs at the snapapi26 kernel module building stage. It takes place when the installed module's version does not match your VM kernel version.

To check the agent's status to see that it has really not registered in Cloud Backup, run the following command in the Yandex Cloud CLI:

yc backup vm get <VM_ID> --folder-id <folder_ID>

If the agent is not installed or registered, the command will return an error or an empty response.

To resolve this issue:

1. Check the installation logs. Connect to the VM via SSH and examine the following files. Most often, the root of the problem lies exactly there:

   /var/log/baas-agent-installer/log.txt
   /var/log/trueimage-setup.log (this is the file where you can usually see snapapi26 build errors)
   /var/log/Acronis
   

2. Build the kernel module manually. If you see errors related to the snapapi26 module in the logs, you should build it yourself for the current kernel version. A detailed manual build guide is available in the backup provider's knowledge base.

If the above actions did not help, create a support ticket. When creating a request, provide the following information:

• ID of the VM.
• Log files listed above.

Cloud Backup VM stuck in the status for a long timeCloud Backup VM stuck in the Registering status for a long time

Most likely, there is no service account attached to the virtual machine. For Cloud Backup to operate correctly, you need to attach a service account with the backup.user minimum role to the virtual machine.

After you add a service account, you should manually install the agent on the VM.