Examples of VM Archiving for VMware

You can use VM archiving to reclaim space and to control pruning.

Using Power Management and Archiving to Reclaim Space

Virtual machines that consume storage but are rarely used can be archived automatically. You can use resource management rules to power off virtual machines that are underused, then archive powered off virtual machines to reclaim space. You can use Performance graphs in vCenter to get an idea of whether specific virtual machines are likely to be powered off and archived based on the VM Management rules.

The following scenarios show examples of space savings.

Scenario 1

In the following vCenter displays, the virtual machine docs_vs_Vm1 is powered on. It has about 426 GB of provisioned space, most of it unused, and the CPU usage is negligible.

The VM Management settings for the subclient that backs up this virtual machine can be used to power off any virtual machines for which the CPU usage is less than 10% for 10 days.

Archiving this virtual machine saves about 426 GB in storage.

Scenario 2

The following vCenter screens show an ESX with around 50 virtual machines and 4 datastores. The total capacity is around 4.55 TB and the total used space is about 3.5 TB.

About 16 virtual machines are powered off and can be archived or migrated immediately.

Archiving these virtual machine saves about 1 TB (900GB) of disk space.

Pruning Archived Data to Reclaim Space

Archived data is pruned and secondary storage space is reclaimed based on the subclient retention setting and the storage policy cycle-based retention criteria. Running a synthetic full backup reduces space on secondary storage for deleted virtual machines that meet the expiration criteria. Running data aging reclaims space on the secondary storage by pruning the expired backup jobs. The following sections describe scenarios for space reclamation.

Scenario 1

To configure retention settings:

  1. Configure the subclient:
    1. Navigate to Client Computers > virtualization_client > VMware > backup_set.
    2. Right-click the subclient and click Properties.
    3. In the Subclient Properties dialog box, click the VM Management tab and the Retention subtab.
    4. Under the For archived VMs deleted by user in vCenter, prune data from MediaAgent heading, set the retention to After 100 days.
    5. Click OK.
  2. Configure the storage policy:
    1. Navigate to Policies > Storage Policies > storage_policy (the storage policy that is used for the subclient).
    2. Right-click the storage policy copy and click Properties, then click the Retention tab.
    3. Verify that the Enable Data Aging option is selected.
    4. Select Retain for under Basic Retention Rule for All Backups and set the period to 15 days and 2 cycles.
    5. Click OK.

The following process describes how deleted data are dropped from the synthetic full backup, enabling the reclamation of secondary storage space.

  1. Run a few backup jobs. This archives virtual machines based on the defined archiving rules.
  2. Delete a few virtual machines in vCenter.
  3. Run an incremental backup job.
  4. After the above incremental job is performed, the deleted virtual machines expire after 100 days.
  5. Run a synthetic full backup. The Storage Policy Default option is selected by default in the Advanced Backup Options dialog box, on the Media tab.

    Running a synthetic full backup starts a new backup cycle.

  6. From the backup job history of the synthetic full job, verify the list of archived virtual machines. Ensure that the deleted virtual machines and their corresponding data are no longer included.

    Running a synthetic full backup has freed space on secondary storage by pruning expired virtual machines and their data.

  7. Run more incremental backup jobs and again perform a synthetic full backup. Running the synthetic full backup again starts the third backup cycle. Since the storage policy retention was set for 2 cycles and 15 days, the first cycle becomes prunable.
  8. Run a data aging job.

    The secondary storage space occupied by the first backup cycle is reclaimed.

Scenario 2

To reclaim space on secondary storage by completely removing the archived virtual machines and their files, follow the steps given below.


  • Retention has been set to n days in the subclient properties.
  • Storage Policy retention has been set to x cycles and y days.
  • A few backup cycles have been completed.

Take the following steps:

  1. In the Subclient Properties dialog box, click the VM Management tab and the Retention subtab, and then change the retention to a minimum of 1 day.
  2. Change the storage policy retention setting to 1 cycle and 0 days.
  3. Delete the unwanted virtual machines from vCenter.
  4. Perform an incremental backup.
  5. After 1 day, perform a synthetic full backup with the Storage Policy Default option selected (the default) in the Advanced Backup Options dialog box, on the Media tab.

    The synthetic full backup image does not retain the deleted virtual machines and prunes their data.

  6. Running a synthetic full backup initiates a new backup cycle. Since the storage policy retention is set for 1 cycle, all the previous backups have expired.
  7. Run a data aging job.

    All older backups prior to the synthetic full backup are pruned. All deleted virtual machines and their corresponding data are pruned and space on secondary storage is freed. All previous backups are pruned.

Last modified: 3/13/2019 8:21:12 PM