Backing Up Virtual Machines

You can back up virtual machines from a subclient or from a backup set (to include all subclients for the backup set). For each subclient, you must add the virtual machines to be backed up in the subclient content.

Resource Limit per CNA Host

Each CNA host can support up to eight (8) streams. If you perform a backup for multiple virtual machines using more than eight streams, the job might go to Pending state, and virtual machines that are skipped because of this resource limit are backed up in a subsequent attempt.

If backups and restores are running simultaneously and the resource limit is reached, you might not be able to complete those actions successfully.

To avoid backup failures, limit the number of streams so that less than eight streams are used in backups. You can adjust the number of streams for each subclient by modifying the Number of Data Readers value on the Advanced Options tab of the subclient properties.

Before You Begin

  • Decide which type of backup is appropriate. Typically, you can choose either an incremental or full backup type. For the first backup of a VM, a full backup is always performed.
  • To perform backups, FusionCompute Tools must be installed on guest VMs.


  1. From the CommCell Browser, expand Client Computers > virtualization_client > Virtual Server > FusionCompute > backup_set.
  2. Start the backup from the subclient or backup set:
    • From the subclient,right-click the subclient and then click Backup.
    • From the backup set, right-click the backup set and click Backup All Subclients; then click Yes to confirm.
  3. In the Backup Options dialog box, choose the backup type.
  4. Optional: To schedule the backup, click Schedule.

    For more information on scheduling, see Scheduling.

  5. Optional: To further customize the backup operation, click Advanced.
  6. Optional: To save the current backup options as a script file, click Save as Script.

    For more information, see Save as Script Overview.

  7. Click OK to start the backup job.

You can track the progress of the job from the Job Controller. When the backup is complete, the Job Controller displays Completed.

After your backup job is complete, you can view the backup job history. For more information, see Job History.

Last modified: 4/17/2019 2:59:04 PM