Set Up Dynamic Disk Mirroring for Virtual Machines on vSphere VMFS

Typically, in the ESXi environment, 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.

Prerequisites

• Use a Windows virtual machine that supports dynamic disks.
• Required privilege: Virtual machine. Configuration. Settings

Procedure

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 Configuration Params and add the following parameters:
      Replace # with the boot device SCSI bus controller ID number. By default, it is set to 0.

      Name	Value
      scsi#.returnNoConnectDuringAPD	True
      scsi#.returnBusyOnNoConnectStatus	False

   5. For 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.
      Replace # with the boot device SCSI bus controller ID number. By default, it is set to 0.

      Name	Value
      scsi#:1.passthruTransientErrors	True
      scsi#:2.passthruTransientErrors	True

   6. Click OK.