2.7 Enabling PXE on Devices

To image a device using Preboot Services, you need to find out if the device is PXE capable, and then make sure that PXE is enabled.

PXE code is typically delivered with newer devices (PC 99 compliant or later) on the NIC.

This section includes the following information:

2.7.1 Enabling PXE on a PXE-Capable Device

When PXE is enabled, it can lengthen the time of the boot process slightly, so most NICs have PXE turned off by default. To enable PXE on a PXE-capable device:

  1. Access the computer system BIOS and look at the Boot Sequence options.

    The PXE activation method for a device varies from one manufacturer to another, but generally one of the following methods is used:

    • Some BIOS have a separate entry in the BIOS configuration to enable or disable the PXE functionality. In this case, set either the PXE boot setting or the Network boot setting to Enabled.

    • Some BIOS extend the entry that allows you to configure boot order.

  2. If PXE is not listed in the Boot Sequence options and if the NIC is embedded in the motherboard, look at the Integrated Devices section of the BIOS, which might have an option to enable PXE. PXE might be called by another name, such as MBA (Managed Boot Agent) or Pre-Boot Service.

    After enabling PXE in the Integrated Devices section, look at the Boot Sequence options and move PXE so that it is first in the boot sequence.

  3. Save any changes you have made and exit the system BIOS.

  4. Reboot the device.

If the device does not have the network adapter and PXE integrated into the motherboard, it uses the installed NIC management software to prompt you to start PXE configuration during the boot process.

For example, many network adapters that are PXE-aware prompt you to press Ctrl+S during the boot process to allow you to configure the PXE functionality. Other network adapters might prompt you to press Ctrl+Alt+B or another key combination to configure PXE.

If the computer system does not have an integrated NIC, you might need to use NIC management software to configure your NIC to support PXE. Refer to your NIC documentation for support of PXE.

On a UEFI machine, do not boot into BIOS PXE mode, as this corrupts the GPT header. Ensure that the mode is set to UEFI Only, or Legacy Only to prevent cross PXE boot scenario.

2.7.2 Verifying That PXE Is Enabled on a Device

After you have activated PXE, it becomes available in the Boot section of the BIOS. PXE is correctly enabled on a device when the device attempts to establish a PXE session during the boot process. You can see this happening when the device pauses during the boot process and displays the following on the screen:

CLIENT MAC ADDR: 00 E0 29 47 59 64

The actual message displayed varies from one manufacturer to another, but you can identify it by the obvious pause in the boot process as the device searches for DHCP.