[LinuxBIOS] remote reset

[Ward Vandewege]

On Mon, Feb 26, 2007 at 02:59:06PM +0100, Segher Boessenkool wrote:
> >> can a machine running linuxbios be remotely reset/reboot from
> >> crashed/frozen state over a network connection?
> >
> > This needs dedicated hardware in the machine and LinuxBIOS is "just"
> > software. Also, LinuxBIOS is done and over with in the system after
> > it has started the payload.
> 
> If your (server-class) machine has a networked IPMI BMC
> then you can do remote reset with it just as well if the
> machine runs LinuxBIOS as it would with the vendor BIOS.
> Well it *should* work, who knows :-)

Yeah, quite. While I *have* got one IPMI card working with LinuxBIOS, in my
experience most IPMI implementations are prime examples of why proprietary
software is bad. I have yet to encounter an IPMI card that is stable and
adheres to the spec. The situation is improving somewhat with IPMI 2.0, but
vendors are still pushing out extremely buggy products, with even buggier
proprietary IPMI client software. The free software IPMItool is a much more
reliable piece of client software, but it lacks support for some IPMI
boards/features, and it can't stop the IPMI boards from being so buggy that
they crash themselves...

My current feeling is that with LinuxBIOS, you get reliable remote console on
the serial port (as opposed to proprietary BIOSes, where console-to-serial is
often slow as molassis, and almost never actually reliable). So; combining
the reliable LinuxBIOS serial console with a device that turns the serial
connection into a network accessible one (for instance, another GNU/Linux box
with a serial port), and another device that can power-toggle your machine is
a reliable remote control solution.

The alternative is a more advanced BMC - stuff like Dell's DRAC4, and HP's
ILO. But these, too, are totally proprietary and often buggy. Try, for
instance, to access an HP ILO with ECN enabled on your machine - it won't
work. And the console redirection they provide is most often a graphical
console, which makes things slow. Also, console redirection requires help of
browser applets that are often unreliable. I have used them successfully
though to power-toggle machines - that part seems more or less reliable.

Thanks,
Ward.

-- 
Ward Vandewege <ward at gnu.org>