Thus far, we have configured our server to give our clients an IP address on boot, and have even built two installation trees, such that we can install either CentOS 7 or Ubuntu 18.04 Server, without the need for any physical media. However, when our target machine boots over the network, how does it know what to boot?
The answer to this comes in the form of the PXELINUX configuration. This is very similar in nature to the GRand Unified Bootloader (GRUB) configuration that most Linux installations use, to define their boot options and parameters when they boot from disk. Using the installation we have built so far, these configuration files are expected to be in /var/lib/tftpboot/EFIx64/pxelinux.cfg (or ...