Typically, you cannot use LUN manager software on virtual machines to mirror virtual disks. However, if your Microsoft Windows virtual machines support dynamic disks, you can mirror virtual disks across two SAN LUNs. Mirroring helps you to protect the virtual machines from an unplanned storage device loss.


  • Use a Windows virtual machine that supports dynamic disks.
  • Required privilege: Advanced


  1. Create a virtual machine with two virtual disks.
    Place the disks on different datastores.
  2. Log in to your virtual machine and configure the disks as dynamic mirrored disks.
    See Microsoft documentation.
  3. After the disks synchronize, power off the virtual machine.
  4. Change virtual machine settings to enable the dynamic disk mirroring.
    1. Right-click the virtual machine and select Edit Settings.
    2. Click the VM Options tab and expand the Advanced menu.
    3. Click Edit Configuration next to Configuration Parameters.
    4. Click Add Row and add the following parameters:
      Name Value
      scsi#.returnNoConnectDuringAPD True
      scsi#.returnBusyOnNoConnectStatus False
    5. If you use ESXi version 6.7 or later, include an additional parameter for each virtual disk participating in the software RAID-1 configuration.
      The parameter prevents guest OS I/O failures when a storage device fails.
      Name Value
      scsi#:1.passthruTransientErrors True
      scsi#:2.passthruTransientErrors True
    6. Click OK.