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Configuring VMDirectPath I/O pass-through devices on a VMware ESX or VMware ESXi host (1010789)
About VMDirectPath I/O passthrough devices
The supported maximums for passthrough devices is:
- ESX\ESXi 4.0: 2 Devices
- ESX\ESXi 4.1: 4 Devices
- ESX\ESXi 5.x: 8 Devices
When selecting the devices, ensure that you follow these restrictions:
- Devices behind PCI bridge or PCIe to PCI/PCI-X bridge should be passed to the same virtual machine.
- Devices that are directly below root port can be used for passthrough as long as the root port supports ACS.
For more information, see PCI Passthrough with PCIe devices behind a non-ACS switch in vSphere (1036811).
- Devices on the same PCI bus can be used in different virtual machines if they do not have reset dependency.
- Do not enable passthrough on the USB controller which is booting from USB device or SD card.
For more information, see Unable to disable USB controller for passthrough after it is enabled (2068645).
Configuring passthrough devices
To configure passthrough devices on an ESX/ESXi host:
- Select an ESX\ESXi host from the Inventory of VMware vSphere Client.
Note: If you have a chipset with VT-d, when you click Advanced Settings in vSphere Client, you can select the devices that are dedicated to the VMDirectPath I/O.
- In the Configuration tab, click Hardware Advanced Settings. The passthrough Configuration page lists all available pass-through devices.
Note: A green icon indicates that a device is enabled and active. An orange icon indicates that the state of the device has changed and the host must be rebooted before the device can be used.
- Click Edit.
- Select the devices and click OK.
- When the devices are selected, they are marked with an orange icon. Reboot for the change to take effect. After rebooting, the devices are marked with a green icon and are enabled.
Note: The configuration changes are saved in the /etc/vmware/esx.conf file.
The PCI slot number where the device was connected is 00:0b:0. It is recorded as:
/device/000:11.0/owner = "passthru"
Note: 11 is the decimal equivalent of the hexadecimal 0b.
To configure a PCI device on a virtual machine:
- From the Inventory in vSphere Client, right-click the virtual machine and click Edit Settings.
- Click the Hardware tab.
- Click Add.
- Choose the PCI Device.
- Click Next.
Note: When the device is assigned, the virtual machine must have a memory reservation for the full configured memory size.
For more information, see Configuration Examples and Troubleshooting for VMDirectPath Guide.
For HP Proliant servers experiencing issues with VMDirectPath, this is a known issue in VMware ESXi 5.1, Patch Release ESXi510-201307001 (2052143) and later. These issues are addressed in VMware ESXi 5.5, Patch Release ESXi550-201501001 (2099265). For more information, see HP Advisory c03835455.
Note: The preceding link was correct as of July 9, 2014. If you find the link is broken, provide feedback and a VMware employee will update the link.
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