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Configuring disks to use VMware Paravirtual SCSI (PVSCSI) adapters
Details
This article includes supplemental information about configuring and using VMware Paravirtual SCSI (PVSCSI) adapters.
PVSCSI adapters are high-performance storage adapters that can result in greater throughput and lower CPU utilization. PVSCSI adapters are best suited for environments, especially SAN environments, where hardware or applications drive a very high amount of I/O throughput. PVSCSI adapters are not suited for DAS environments.
This table shows the support matrix for use of Paravirtual SCSI adapters for data disks and boot disks for the various guest operating systems and ESX versions.Support shown in the table is from the listed ESX/ESXi version and later versions.
Guest operating system
Data Disk
Boot Disk
Windows Server 2008 R2 (64-bit only)
ESX/ESXi 4.0 Update 1
ESX/ESXi 4.0 Update 1
Windows Server 2008 (32 and 64 bit)
ESX/ESXi 4.X
ESX/ESXi 4.0 Update 1 ESX/ESXi 4.1
Windows Server 2003 (32 and 64 bit)
ESX/ESXi 4.0 ESX/ESXi 4.1
ESX/ESXi 4.0 ESX/ESXi 4.1
Windows 7 (32 and 64 bit)
ESX/ESXi 4.1
ESX/ESXi 4.1
Windows Vista (32 and 64 bit)
ESX/ESXi 4.1
ESX/ESXi 4.1
Windows XP (32 and 64 bit)
ESX/ESXi 4.1
ESX/ESXi 4.1
Red Hat Enterprise Linux (RHEL) 5 (32 and 64 bit) and all update releases
ESX/ESXi 4.X
Not Supported
RHEL 6 (32 and 64 bit)
ESX/ESXi 4.0 Update 2 ESX/ESXi 4.1
ESX/ESXi 4.0 Update 2 ESX/ESXi 4.1
SUSE Linux Enterprise 11 SP1(32 and 64 bit) and later releases
ESX/ESXi 4.0 Update 2ESX/ESXi 4.1
ESX/ESXi 4.0 Update 2ESX/ESXi 4.1
Ubuntu 10.04 (32 and 64 bit) and later releases
ESX/ESXi 4.0 Update 2 ESX/ESXi 4.1
ESX/ESXi 4.0 Update 2ESX/ESXi 4.1
Distros using Linux version 2.6.33 or later and that include the vmw_pvscsi driver
ESX/ESXi 4.1
ESX/ESXi 4.1
Because the default type of newly hot-added SCSI adapter depends on the type of primary (boot) SCSI controller, hot-adding a PVSCSI adapter is only supported for those versions that support booting from a PVSCSI adapter.
Paravirtual SCSI adapters also have these limitations:
Hot add or hot remove requires a bus rescan from within the guest.
Disks with snapshots might not experience performance gains when used on Paravirtual SCSI adapters if memory on the ESX host is overcommitted.
If you upgrade from RHEL 5 to an unsupported kernel, you might not be able to access data on the virtual machine's PVSCSI disks. You can run vmware-config-tools.plwith the kernel-version parameter to regain access.
Solution
To configure a disk to use a PVSCSI adapter:
Launch a vSphere Client and log in to an ESX/ESXi host or vCenter Server.
Select a virtual machine, or create a new one.
Ensure a guest operating system that supports PVSCSI is installed on the virtual machine.
In the vSphere Client, right-click on the virtual machine and click Edit Settings.
Click the Hardware tab.
Click Add.
Select Hard Disk.
Click Next.
Choose any one of the available options.
Click Next.
Specify the options your require. Options vary depending on which type of disk you chose.
Choose a Virtual Device Node and specify whether you want to use Independent mode. For data disks choose a Virtual Device Nodebetween SCSI (1:0) to SCSI (3:15). For a boot disk choose Virtual Device Node SCSI (0:0), or choose the Virtual Device Node that will boot in the order you require.
Click Next.
Click Finish to finish the process and exit the Add Hardware wizard. A new disk and controller are created.
Select the newly created controller and click Change Type.
Click VMware Paravirtual and click OK.
Click OK to exit the Virtual Machine Properties dialog.
Power on the virtual machine.
Install VMware Tools. VMware Tools includes the PVSCSI driver.
Scan and format the hard disk.
Note: In some operating systems, you need to create a virtual machine with the LSI controller, install VMware Tools, then change to the drives to paravirtualized mode to perform the procedure above.
To boot a Windows virtual machine from a disk attached to a PVSCSI adapter, the VMware PVSCSI driver must be installed in the Windows guest. Floppy disk images that contain the driver are available for the versions of ESX/ESXi that support this. Floppy images are located in the /vmimages/floppies/ directory. If the floppy images are not visible, see Unable to mount a floppy image in vCenter Server (1036836).
