3. The Technology under the hood

To build a diskless network, it is important to understand how such a system works. This section deals with the basics of how such a system functions.

3.1 How does it work ?

Each time it boots up, the diskless system follows these steps:

1. The BIOS, configured to boot from either a floppy or a network card's BOOT ROM, reads the boot information from the specified device.
2. The media then does the following
   • Broadcasts its MAC address on the network, searching for a DHCP server.
   • Receives an IP address from the DHCP server and configures the NIC accordingly.
   • Fetches a predefined kernel image from the server using TFTP (Trivial File Transfer Protocol).
   • Loads this kernel image into the RAM.
3. Once the kernel image is loaded into the RAM, the root file system is fetched via NFS.
4. Depending on the methodology adopted, system initialization scripts are run and the system is made ready for use.

3.2 Methods of achieving diskless systems

Diskless systems can be achieved in 3 ways:-

1. LTSP The Linux Terminal Server Project.
2. Network Booting with Etherboot
3. CD Based distributions