Editing VM Group Settings for VMware

For an existing VM group, you can modify options that affect backups.

VMware Transport Considerations

Licensing: In vSphere 5.0, the SCSI HotAdd feature is enabled only for vSphere editions Enterprise and higher, which have Hot Add licensing enabled. No separate Hot Add license is available for purchase as an add-on. In vSphere 4.1, Hot Add was also enabled in the Advanced edition. Customers with vSphere Essentials or Standard editions are not able to perform proxy-based backup, which relies on SCSI HotAdd. Those customers must use alternate transport modes.

SCSI Controllers: HotAdd relies on the SCSI protocol. With VDDK 6.5 or later, VMware recommends the paravirtual SCSI (PVSCSI) controller. (For more information, see Virtual Disk Development Kit Release Notes.) For older VDDK versions, use the LSI SCSI controller. HotAdd does not support IDE disks.

Before You Begin

To validate backups, perform the following setup:

  • To mount VMs to a recovery target, create a recovery target. To mount all of the VMs in the VM group as a virtual lab, specify the Virtual lab options for the recovery target.
  • To use your own script for validation, copy the script to a location that can be accessed from the access node using a UNC network path.

For more information, see Backup Validation.


  1. From the navigation pane, go to Protect > Virtualization.

    The Virtual machines page appears.

  2. On the Hypervisors tab, click the hypervisor.

    The hypervisor properties page appears. The VM groups area displays summary information for any existing VM groups.

  3. Click a VM group.

    The VM group properties page appears.

  4. On the Configuration tab, modify settings:
    • Snap mount esx host: For VM groups that use a server plan with snap recovery points configured, click Edit and then select an ESX server that can be used to mount snapshots for IntelliSnap backups.

    The Settings area shows settings that are used to back up the virtual machines in the VM group.

  5. In the Settings area, click Edit.

    In the Edit options dialog box, provide the following information:

    • Use changed block tracking: Select this option to use changed block tracking (CBT) for backups.

      With CBT, backups only write blocks that have changed since the previous backup. For virtual machines where there is a known issue with CBT, you can turn off CBT to run backups using the cyclic redundancy check (CRC) method instead.

    • No. of readers: Set the number of readers to control how many parallel read operations can be launched during backups.
    • Virtual machine backup type: Select the type of backup to perform:
      • Application Aware: Uses in-guest application plug-ins to assist the Virtual Server Agent in quiescing the file system and applications and supporting granular application data recovery.

        To specify credentials for guest VMs in the VM group, click the key button (), and then provide the guest credentials.

      • File system and application consistent: Quiesces the file system and applications while performing the backup.
      • Crash-consistent: Takes a point-in-time snapshot of virtual machine data without quiescing.
    • Transport mode for VMware: Select one of the following options:
      • Auto: The transport mode is selected automatically based on the backup environment:

        If the datastore is accessible to a physical proxy, SAN is used.

        If the datastore is accessible to the ESX server for a virtual proxy, HotAdd is used.

        Otherwise, NBD is used.

      • SAN: For directly connected storage using Fibre Channel (FC) or Internet SCCI (iSCSI) protocols. The Virtual Server Agent must have access to the datastore LUNs (logical drives) that provide storage for virtual machine disks. Data is read directly from the storage where virtual machines reside, without going through the ESX host or transferring data over the local area network (LAN). The ESX host is contacted only to coordinate access to the LUN. SAN transport mode cannot be used if the proxy computer is a virtual machine.
      • Hot Add: The Virtual Server Agent is installed on a virtual machine residing on an ESX server. In HotAdd mode, the data volumes containing the virtual machines to be backed up are automatically mounted to the proxy, so they can be accessed by the proxy as a local disk. The ESX host the proxy is running on must have access to all datastores for the virtual machine. If the virtual machine and the proxy are not on the same host, all datastores must be shared between the hosts.
      • NBD: Data is transferred using the TCP/IP connection between the ESX server and the proxy computer. The local area network (LAN) can be the production network or a dedicated backup network.
      • NBD SSL: Similar to NBD mode, but data transfer between the proxy computer and the ESX server is encrypted. Encryption should be used for sensitive information, even within a private network.
      • NAS: NAS (network attached storage) transport mode enables the virtual server agent (VSA) proxy computer to read data directly from the network file server (NFS), without going through an ESX host or transferring data over the local area network (LAN).
    • Datastore freespace check: Select this option to ensure that there is sufficient free space on the datastore before performing the backup.
    • Datastore freespace required: Type the percentage of free space that should be available on the datastore before performing the backup.
    • Collect file details: Select this option to collect file and folder information during streaming backups or when creating a backup copy from IntelliSnap backups. Use this option when creating a copy for tape storage, because file and folder information is required when recovering files from tape.
    • Collect file details for snapshot copy: Select this option to collect file and folder information when creating a snapshot copy from IntelliSnap backups. Use this option when creating a copy for tape storage, because file and folder information is required when recovering files from tape.

      Note: Collecting file details increases the time required to perform backups, and is not required to enable recovery of guest files and folders.

  6. To enable validation for virtual machines that run applications, perform the following steps:
    1. In the Backup validation section, turn on the Validate VM Backups option.

      The Configure backup validation dialog box appears.

    2. Choose one of the following options for validation:
      • If the Use source VM ESX to mount option is enabled, backups are mounted on the ESX host where the source VM resides.

        Note: Only administrators can use this option. Non-admin users must use a recovery target to perform backup validation.

      • If the Use source VM ESX to mount option is disabled, a recovery target is used to validate backups.

        If you are using a recovery target to validate backups, from the Recovery target list, select the recovery target that can be used to mount VMs for validation.

    3. Optional: To run a script to validate a specific application inside guest VMs, in the Guest credentials section, specify the username and password for a user account that can be used to start and run the application on the guest VMs.
    4. Optional: To modify the default schedule for backups and validation, under Backup validation schedule, click the schedule and then make any required changes.
    5. Optional: To supply your own validation script, for the Custom validation script option, click Add, and then provide the following information:
      • Script description: Enter a brief description of the script, such as "Validation script for Exchange."
      • UNC network path: Enter the UNC network path for the custom script, including the script file name.
      • User name: Enter the user name for the account that runs the script.
      • The user account must have privileges for the application that the script validates.
      • Password: Enter the password for the user account, and then enter the same password in the Confirm password box.

      Logs for the script execution are created in the folder identified by the UNC network path. The log files are named by combining the script name with other parameters, such as the VM name. The script returns an exit code of 0 after successful script execution, and returns a nonzero exit code with additional details if the script failed.

      Note: To include a script with additional arguments, call the script with its arguments in a batch or shell file, and point to that file in the UNC network path box.

    6. Click Save.
  7. To modify the plan or policy associated with the VM group, click Edit in the Plan area or the Policies area.

    The name of the area depends on whether the VM group was defined to use a backup plan that was created in the Command Center or a storage policy that was created in the CommCell Console. You cannot change that selection for an existing VM group, but you can select a different plan or policy, as follows:

    • When editing the Plan setting, you can select a plan that was previously defined in the Command Center.
    • When editing the Policies setting, you can make the following changes:
      • From the Storage policy list, you can select a storage policy that was previously defined in the CommCell Console or a plan that was defined in the Command Center.
      • Optional: You can select a schedule policy that was previously defined in the CommCell Console.
  8. Click Save.

Last modified: 3/9/2020 3:18:01 PM