[Etherboot-users] Re: [Ltsp-discuss] Questions about pxe and etherboot

[Richard B. <ra...@xs...>]

Marty,

thanks for your reply.

Op zondag 22 januari 2006 03:13, schreef Marty Connor:
..... [skipped] .....
> >   In my case I have succesfully created floppy boot images.  Is
> > it now possible (in the client system)  to swap these floppy
> > bootimages for
> > networkcard pxe images (by programming an eprom image from rom-o-
> > matic) and
> > have the same machine still booted via the network?  I mean is no
> > there no
> > bios option that needs to be changed (for example: change boot
> > order.  Make
> > lan the first thing to try instead of the floppy disk drive).  As
> > far as I
> > remember I have not seen a 'boot from the lan' option in the bioses
> > that I
> > have looked at.   Is it like this, that when a pxe image is present
> > in a
> > network card, it automatically boots the machine?
> > I did not find this explained on this page:
> > http://wiki.ltsp.org/twiki/bin/view/Ltsp/PXE hence I my question.
>
> BIOSes have evolved, and have different ways of expressing network
> booting capability.  If you have a reasonably recent Intel
> motherboard, for instance, with a Phoenix BIOS, and you put a NIC
> card in with a PXE boot ROM on it, when you go to the BOOT menu, you
> can actually see the boot ROM as a boot option along with the floppy
> and hard drive, and you can set its order.  

Checked 2 computers today and the "lan" boot option is present.  unfortenately 
those computers are not part of the ltsp setup...

> This is part of the BIOS 
> specification, and if your boot ROM is "PNP Conformant" (and your
> BIOS is), you can set the boot priority of things like Adaptec SCSI
> cards, and Ethernet Cards, and your BIOS will respect it.

Hmm,  how can I see that a bios or bootrom is PNP conformant (check the 
documentation that comes with the computer?).  

> Not all BIOSes correctly implement PNP, but quite a few do.  A BIOS
> update in many cases will help. If the BIOS copyright date is in the
> early 1990s, you may have some difficulty, and in that case,
> Etherboot will likely just run.
>
> > For the moment I just assume that pxe boots the system when it is
> > present.
> > This is for my next question.  In case a noteboot does not support
> > pxe on its
> > own ethernet card (pcmcia card), would the following card make any
> > notebook
> > pxe enabled:
> > http://www.argontechnology.com/product.aspx/cid1/103/pid/304 ?
> > It sounds strange to me, that when a notebook is not aware of pxe
> > on its one
> > because it was never designed for it, that it would now
> > automatically work
> > when the above mentioned card is plugged in....
>
>    Product Description
>    Argon's EP-4103DL-PXE Cardbus Fast Ethernet PC Card with PXE
>    10/100 Fast Ethernet Dongle-less PCMCIA
>    Complies with IEEE 802.3 10BaseT and 802.3u 100BaseTX Standards
>    Supports 10/100M Auto-Negotiation 32bit High Performance 100Mbps
> Networking
>
>    PXE Support included with Argon's PXE on Disk: works with Argon
> Client Management
>    Services (CMS) PXE Server or Microsoft Remote Installation
> Services (RIS).
>
> Hmm, I believe that you'll need to boot from their floppy to get PXE
> to work.
>
> The technical reason is that when most notebook boot, unless their
> Ethernet ports are on the motherboard, they have to initialize a PCI
> to PCMCIA bridge chip.
>
> The question is, where is the code to do this?  Well, it kind of has
> to be done by the BIOS, which would then have to know how to control
> whatever PCMCIA Ethernet card you happen to have plugged into your
> PCMCIA slot.
>
> There's the rub.  Unless your laptop BIOS specifically knows what
> bridge chip is being used, and what PCMCIA card is being used, most
> laptops without Ethernet wait for a kernel or other boot code (like
> Argon's PXE on Disk (kind of like an Etherboot floppy)), to do it.
>
> Etherboot, unfortunately doesn't yet know how to deal with PCMCIA
> buses.  It's one of the things we hope to add, but so far, we do PCI
> and ISA buses mainly, which takes care of the majority of cases.
> We'd like to do PCMCIA and USB, and I'm sure we'll get there in time.
> Someone will decide they want it, and do it or fund it, just like PXE
> support.
>
> > I'll highly appreciate any explanation on pxe.  The wiki pages are
> > good, but
> > unfortenately they just missed the 2 points mentioned above.
>
> I hope this is helpful.  I think my answers are correct.  I hope and
> expect that someone will correct me if I am mistaken.

Sofar it clarifies a lot for me.

> > Another question I have (just out of curiousty); what ethercards
> > support pxe
> > out the box nowadays all?  Or should they all get an eprom to
> > enable pxe?
> > Same question for notebooks, which notebooks support pxe nowadays,
> > is that
> > all or for example only the IBM thinkpad (that's the answer from
> > google) ;)
>
> For an Ethernet card to support PXE out of the box, it needs a flash
> EEPROM.  This raises the cost, but not so much as in the old days.  I
> think I noticed an RTL8169 (Gigabit Card) that has PXE on it for not
> too much more than $20 the other day.

hmmm, that sounds attractive.  But the ltsp shop site list an network card 
with bootrom for $20 as well (If I not mistaken).

> Now, if you're a bargain hunter, you can find old Intel EEPRO100s and
> 3COM 3C905CTXM cards, which have PXE in flash memory, and will
> network boot by loading PXELINUX.0 from the SYSLINUX/PXELINUX/
> ISOLINUX package.

Will the ltsp boot sequence do as well, or must it have to be 
SYSLINUX/PXELINUX/ISOLINUX package.  I think the ltsp server provides 
PXELINUX.0.  At least that is what I saw in /tftp/.... directory.

-- 
Richard Bos
Without a home the journey is endless