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Boot and install the system over the network (PXE)

Via TFTP on the Pyrrha server, we provide several installers and live systems that can be booted over the network without the need to produce bootable media:

  • GParted Live: a rescue live distribution with a partition management tool of the same name,
  • Ubuntu LTS (long support release): a live system in a desktop variant and a server installer,
  • Debian: network installer,
  • Fedora: the Server and Everything installers, which can also install the desktop variety,
  • AlmaLinux, Rocky, CentOS Stream: RHEL derivatives.
  • Memtest86+: a tool for testing RAM.

If you manage a computer at FI, you can instruct our DHCP server to point that computer to Pyrrha when requesting a network boot by setting its attributes in the faculty administration. In the machine attribute editing application, enter the MAC address of the machine and select one of the preset boot loaders in the PXE section:

  • Recommended: grub/shim.efi.signed for current UEFI network boot machines,
  • pxe_users/lpxelinux.0 for older ("legacy") boot mode (if you must use this option, it is possible that the machine is too old to run current Fedora and RHEL derivatives that require newer microarchitecture).

You may need to enable network boot in BIOS/UEFI. To boot systems other than Ubuntu, Secure Boot must be disabled (a "bad shim signature" error message will appear). Network booting only works over IPv4.

For the record: how it works

During a network boot, the computer requests boot instructions from the DHCP server in addition to the address. The DHCP server refers the computer to a boot loader file on Pyrrhus, which the computer downloads and runs via TFTP - either legacy PXELinux or GRUB (via the intermediate shim step). The boot loader then allows you to select from our menu of systems and installers.

In order for the boot to proceed with the selected system, the kernel and initial memory ( initrd) must first be supplied to the computer. Again, these can be downloaded from Pyrrh, but since the boot loaders can download over HTTP, we use the distribution mirrors on Ulysses and have the boot loader download the kernel and initrdfrom there if possible.

Debian, Fedora, and RHEL derivatives allow such booting from Odysseus; other systems do not have the kernel and initrd directly accessible from the mirror. Therefore, we have to manually pull and place them on Pyrrha. However, the minimalist system in initrd can already pull the rest of the data over HTTP from the ISO disk image, so most of the data travels from Odyssey after boot anyway.