discuss: [Proposal] PXE Server HOWTO
Subject:
Re: [Proposal] PXE Server HOWTO
From:
Jason Bechtel ####@####.####
Date:
29 Jan 2002 12:10:05 -0000
Message-Id: <3C56890D.1080401@iig.uni-freiburg.de>
Peter,
Again, comments below interspersed...
Peter Lister wrote:
> I really don't want to offend anyone, but if we are to write a document,
> I feel we have a duty to be accurate and fair. When I see incorrect
> information, I'm going to correct it (or wish to hear a very convincing
> argument). I appreciate that this poster hadn't read my previous
> comment, so please don't take it personally - but this is too important
> to ignore. This was partly the raison d'etre for my starting a howto in
> the first place.
Agreed. I won't take it personally. :-) The outcome of the HOWTO is
what's important.
>>>From my perspective, PXE is an alternative method of remote
>>>booting diskless workstations (the older and perhaps still
>>>more common method is etherboot
>
> PXE is not an "alternative" to Etherboot. An odd feature of PXE is its
> need for a secondary loader such as Etherboot (or pxelinux, or whatever
> knows how to load Windows). Once one knows this, the choice between (a)
> running Etherboot "native" if at all possible or (b) running PXE to
> chain Etherboot (so taking several seconds longer to achieve the same
> effect) really isn't hard to make.
Absolutely right. It's more like an "obstacle" to Etherboot. :-)
Sorry about the phrasing with the word "alternative". Having been on
the LTSP mailing list for a while, I've heard PXE tossed around so much
that I've come to refer to it in a short-hand jargonish imprecise way.
Sorry.
> Calling Etherboot "older" seems to imply that you consider it moribund.
> Far from it, as doubtless Markus or Ken will explain to visitors who
> drop by their Linux Expo booth (I'd love to visit, but I'm on the wrong
> side of the Atlantic). We at Sychron considered it worth writing the
> Etherboot PXE support precisely because we saw Etherboot as the best of
> the bunch in the near future.
Here I think you read to much into the word "older." As with UNIX,
older is better. It means it's been around much longer and is therefore
more solid, stable, tested, and widely used. The word "old" does not in
any way imply moribundity. It simply means that its inception took
place prior to that of PXE.
[Note: I sense here a defensiveness on the behalf of the open,
non-proprietary etherboot with which I can readily identify. It feels
just like when I get defensive about LTSP and Linux in general. It's
completely understandable.]
>>><http://etherboot.sourceforge.net/>). But I've heard that
>>>PXE is quickly becoming a standard, at least for corporate
>
> Aargh! PXE IS NOT A STANDARD.
>
> Sorry to shout, but I have heard this stated before. Though usually the
> usage is turns out to be merely a figure of speech, as I am sure is the
> case here, it is wrong and misleading to newcomers. PXE is an Intel spec
> which refers to accepted RFC standards (DHCP and TFTP). I agree that PXE
> is ubiquitous in new hardware, and many sites add PXE to purchasing
> policies as an undeniably useful shorthand to ensure that new kit can be
> installed without surprises.
You caught me again... Indeed, I was using the word "standard" to refer
to the fact that it has started to appear in desktops systems labeled
and intended for "corporate" use, and I did so at the word of someone on
the LTSP list who I've never met and who quickly ran up against some
fierce backlash on the list.
I suppose this use of the word is a sort of figure of speech, but it is
used so casually in my circles that I didn't give it much thought.
Sorry again. I'm guilty of repeating rumors and misleading
nomenclature! Bad Jason!
By the way, please don't think that I especially encourage PXE usage.
The best way to netboot that I've seen is to put Etherboot on an EEPROM
on your NIC and roll. But I've also seen people send messages to the
LTSP discussion list asking how they can get their PXE cards to work
with LTSP. When the assumed goal is simply "getting LTSP to work" then
working with the hardware they already have is the friendliest way of
handling the situation. As soon as we start telling LTSP newbies things
like "Go get a *real* NIC!" or "Why didn't you buy a system with a
LinuxBIOS?" they will turn away. Okay, perhaps that's unfair. What I
mean is that comments with the message that PXE is bad, etc. are not
helpful to people who are stuck with it. So, I suppose in the interest
of LTSP advocacy I've taken a soft line with regard to PXE and learned
to accommodate it so long as it doesn't get in the way of reaping the
benefits of LTSP and Linux on the desktop.
Now that you've rightly restored my perspective of PXE as an unwanted
interloper in our etherboot-powered netbooting world, let's return to
the readers of the proposed PXE HOWTO. Hopefully this HOWTO is read by
people doing research *before* they make a large purchase of PXE
systems. For those people, these comments about the weaknesses and, in
fact, irrelevance of PXE to netbooting will be helpful. For the others
who find themselves with a PXE NIC and come seeking help, these comments
come slightly too late (unless they can get funds to alter their
hardware situation). So, perhaps the HOWTO's structure should reflect
this by having reader-centric sections:
1. For Prospective Users/Buyers of PXE Hardware
2. For Current Owners of PXE Hardware
Or perhaps a section blatantly titled
"How to Avoid PXE"
As long as the next section is called
"If You're Stuck With It"
Jason
