The PXE configuration file defines the menu displayed to the target ESXi host as it boots up and contacts the TFTP server. You need a PXE configuration file to PXE boot the ESXi installer.
The TFTP server constantly listens for PXE clients on the network. When it detects that a PXE client is requesting PXE services, it sends the client a network package that contains a boot menu.
In the PXE configuration file, you must include paths to the following files:
mboot.c32 is the boot loader.
boot.cfg is the boot loader configuration file.
File Name for the PXE Configuration File
For the file name of the PXE configuration file, select one of the following options:
01-mac_address_of_target_ESXi_host. For example, 01-23-45-67-89-0a-bc
The target ESXi host IP address in hexadecimal notation.
The initial boot file, pxelinux.0 or gpxelinux.0, tries to load a PXE configuration file. It tries with the MAC address of the target ESXi host, prefixed with its ARP type code, which is 01 for Ethernet. If that attempt fails, it tries with the hexadecimal notation of target ESXi system IP address. Ultimately, it tries to load a file named default.
File Location for the PXE Configuration File
Save the file in var/lib/tftpboot/pxelinux.cfg/ on the TFTP server.
For example, you might save the file on the TFTP server at /tftpboot/pxelinux.cfg/01-00-21-5a-ce-40-f6. The MAC address of the network adapter on the target ESXi host is 00-21-5a-ce-40-f6.