When you add a hard disk to a virtual machine, you can create a new virtual disk, add an existing virtual disk, or add a mapped SAN LUN.

In most cases, you can accept the default device node. For a hard disk, a nondefault device node is useful to control the boot order or to have different SCSI controller types. For example, you might want to boot from an LSI Logic controller and use a Buslogic controller with bus sharing turned on to share a data disk with another virtual machine.

Note

You cannot use migration with vMotion to migrate virtual machines that use raw disks for clustering purposes.

1

In the vSphere Client inventory, right-click the virtual machine and select Edit Settings.

2

Click the Hardware tab and click Add.

3

Select Hard Disk and click Next.

4

Select the type of disk to use.

Option

Action

Create a new virtual disk

a

Type the disk capacity.

b

Select a disk format.

Thick Provision Lazy Zeroed creates a virtual disk in a default thick format.

Thick Provision Eager Zeroed creates a type of thick virtual disk that supports clustering features such as Fault Tolerance.

Thin Provision creates a disk in thin format. Use this format to save storage space.

c

Select a location to store the disk. Store with the virtual machine or Specify a datastore.

d

If you selected Specify a datastore, browse for the datastore location, and click Next.

Use an Existing Virtual Disk

Browse for the disk file path and click Next.

Raw Device Mappings

Gives your virtual machine direct access to SAN.

a

Select the LUN to use for the raw disk, and click Next.

b

Select the datastore and click Next.

c

Select the compatibility mode.

Physical allows the guest operating system to access the hardware directly.

Virtual allows the virtual machine to use VMware snapshots and other advanced functions.

d

Click Next.

5

Accept the default or select a different virtual device node.

In most cases, you can accept the default device node. For a hard disk, a nondefault device node is useful to control the boot order or to have different SCSI controller types. For example, you might want to boot from an LSI Logic controller and share a data disk with another virtual machine using a BusLogic controller with bus sharing turned on.

6

(Optional) To change the way disks are affected by snapshots, click Independent and select an option.

Option

Description

Independent - Persistent

Disks in persistent mode behave like conventional disks on your physical computer. All data written to a disk in persistent mode are written permanently to the disk.

Independent - Nonpersistent

Changes to disks in nonpersistent mode are discarded when you power off or reset the virtual machine. With nonpersistent mode, you can restart the virtual machine with a virtual disk in the same state every time. Changes to the disk are written to and read from a redo log file that is deleted when you power off or reset.

7

Click Next.

8

Review the information and click Finish.

9

Click OK to save your changes and close the dialog box.