[realtek] Re: [tulip] Flash EEPROM problems

Donald Becker becker@scyld.com
Tue, 27 Jun 2000 13:51:16 -0400 (EDT)

On Tue, 27 Jun 2000, Brian Hall wrote:

> OK. Is it possible to put a Linux kernel into an EEPROM and boot Linux directly
> off the network card, without using tftp and another machine?

In theory, yes.
However the biggest flash chip most boards accept is 128KB (1Mbit).  Even
compressed, that's not enough to hold a minimal kernel.

There is really only enough space in a boot PROM to for a bootp+TFTP system
that loads the kernel over the network.

After battling this for many years while building clusters, we have given up
on making boot PROMs for network cards.  We now have a boot floppy (or
CDROM) that loads a minimal kernel and standard drivers.  With a real kernel
it uses a regular TCP connection (not the unreliable TFTP method) to
transfer a full kernel.  Then it starts the full kernel using "Two Kernel
Monte" (see the Scyld web page for TKM).  With the real Beowulf setup, the
full kernel waits on Bproc commands to setup the disks, recover checkpoint
files, or start the cluster.

Donald Becker				becker@scyld.com
Scyld Computing Corporation		http://www.scyld.com
410 Severn Ave. Suite 210		Annapolis MD 21403