6.7

Table Of Contents
PXE booting requires some network infrastructure and a machine with a PXE-capable network adapter.
Most machines that can run ESXi have network adapters that can PXE boot.
Note PXE booting with legacy BIOS firmware is possible only over IPv4. PXE booting with UEFI
firmware is possible with either IPv4 or IPv6.
Overview of the PXE Boot Installation Process
Some of the details of the PXE boot process vary depending on whether the target host is using legacy
BIOS or UEFI firmware, and whether the boot process uses TFTP only or TFTP plus HTTP.
When you boot the target host, it interacts with the different servers in the environment to get the network
adapter, boot loader, kernel, IP address for the kernel, and finally the installation script. When all
components are in place, installation starts, as shown in the following illustration.
Figure 31. Overview of PXE Boot Installation Process
ESXi target host
DHCP server
TFTP server
Web server or
TFTP server
DHCP server
script depot
ESXi host
Installer
starts
TCP
ks.cfg
Give me an
installation script
UDP
IP
Give me an IP
for the kernel
TCP or UDP
kernel
Give me
the kernel
UDP
mboot and supporting files
Give me the
network boot loader
UDP
IP & TFTP server
Give me an
IP for the
network adapter
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