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spudtheimpaler 03-01-2007 02:26 PM

debian netboot - cant find root
 
Ok,

I seem to have debian netboot halfway running. I have pxe setup and the linux kernal loading - however:

Code:

VFS: Cannot open root device "" or 68:03
Please append a correct "root=" boot option
Kernel panic VFS: Unable to mount root fs on 68:03

Now I'm a technical guy, ok with unix scripting but know very little about linux filesystems etc. So, if anyone could throw me a bone, I'd really appreciate it.

(By bone, anything will do!)

I have searched plenty but this is night three on this and it's driving me nuts. I was after installing feather-linux or dsl for one thing! I'm only choosing debian as they seem to have written most of the files for me......

Anyway, TIA,

Mitch.

Dutch Master 03-01-2007 02:32 PM

What you need to do is point the kernel to where the / partition is. This means you tell it on what device and partition. Suppose / is on /dev/hda2, you add "root=/dev/hda2" to the script.

spudtheimpaler 03-01-2007 02:59 PM

more info
 
ok, taking the debian-provided script (pxelinux.cfg/default) we have:

Code:

display debian-installer/i386/boot-screens/syslinux.txt
default linux

F1 debian-installer/i386/boot-screens/f1.txt
F2 debian-installer/i386/boot-screens/f2.txt
F3 debian-installer/i386/boot-screens/f3.txt
F4 debian-installer/i386/boot-screens/f4.txt
F5 debian-installer/i386/boot-screens/f5.txt
F6 debian-installer/i386/boot-screens/f6.txt
F7 debian-installer/i386/boot-screens/f7.txt
F8 debian-installer/i386/boot-screens/f8.txt
F9 debian-installer/i386/boot-screens/f9.txt
F0 debian-installer/i386/boot-screens/f10.txt

label linux
        kernel debian-installer/i386/linux
        append vga=normal initrd=debian-installer/i386/initrd.gz ramdisk_size=9458 root=/dev/rd/0 devfs=mount,dall rw  --
label expert
        kernel debian-installer/i386/linux
        append DEBCONF_PRIORITY=low vga=normal initrd=debian-installer/i386/initrd.gz ramdisk_size=9458 root=/dev/rd/0 devfs=mount,dall rw  --
label linux26
        kernel debian-installer/i386/2.6/linux
        append vga=normal initrd=debian-installer/i386/2.6/initrd.gz ramdisk_size=10938 root=/dev/rd/0 devfs=mount,dall rw  --
label expert26
        kernel debian-installer/i386/2.6/linux
        append DEBCONF_PRIORITY=low vga=normal initrd=debian-installer/i386/2.6/initrd.gz ramdisk_size=10938 root=/dev/rd/0 devfs=mount,dall rw  --

prompt 1
timeout 0

the file system they supply looks like this:

Code:

:debian-installer
:    :i386
:    :    :2.6
:    :    :    :initrd.gz
:    :    :    :linux
:    :    :boot-screens
:    :    :    :f1.txt
:    :    :    :<...>
:    :    :    :f10.txt
:    :    :pxelinux.cfg
:    :    :    :default
:    :    :pxelinux.cfg.serial-9600
:    :    :    :default
:    :    :    :pxelinux.0
:    :    :initrd.gz
:    :    :linux
:    :    :pxelinux.0
:pxelinux.cfg
:    :default
:mini.iso
:netboot.tar.gz
:pxelinux.0

Half my confusion is due to there being a number of pxelinux.0 files. I know nothing about network booting, i have hacked this together with a hundred different walkthroughs. Also the two pxelinux.o files look internally to be identical, with root= always pointing to what i guess is the ramdisk.

I have nothing to lose on the pc so i don't mind if the install is stored on ramdisk or hard disk, but i really am looking for some idiot-grade guidance on this. I'm keen to learn, and will welcome any explanations, but mostly i just want it to work right now.

Thanks again Dutch Master for your quick response! (please feel free to come back for a second shot!)

Mitch.

Dutch Master 03-01-2007 11:03 PM

Did you grasp the basics of PXE? I.e. do you understand what happens when a machine performs a netboot? For those who don't, have a look at this: http://www.debian-administration.org/articles/478 and http://www.riddleware.com/solx86/PXE/pxe-netboot.html

In short: you'll need a suitable server for the kernel to be downloaded from, machines that are capable of performing a PXE netboot and the correct parameters in the PXE bootfile.

spudtheimpaler 03-02-2007 03:11 AM

getting closer - is the default file in a wrong format?
 
Sorry if I hadn't made myself clear.

I have RTFM'd as much as possible, but every walkthrough, including those you supplied, tend to be pretty superficial in their detail. Please bare in mind My TFTP server is running from a windows box, trying to install a linux box. I have yet to find one site describing this.

My problem stems from the fact that I don't know which files I should be using from the debian netboot directory. There are duplicates in different folders for example.

So in short, I have a tftp server. I have a folder in that server called tftpboot and in that folder I have the netboot folder as described in my previous post.

Assuming it is all working, which i believe it is (the client machine does find the server) is there anything you can see in the default file below that might be causing it grief? It's not showing a boot menu or alike so I'm wondering if it is misreading the default file. could it be in a too old/new format - is there a different spec the default file could be in? I believe after reading the default file it errors telling me it can't locate the linux kernal and gives me a "boot: " prompt.

spudtheimpaler 03-02-2007 07:11 PM

Given up on netboot
 
I have given up on the netboot, fixed my cd drive, installed DSL and now have another coaster. Oh well, thanks to those who looked!

redcane 04-18-2007 07:08 AM

If it can't find the kernel, it seems there may be a problem withthe TFTP server responding to it's requests for susequent files, though obviously the boot image is loading via TFTP.

It seems you have moved on, but if anyone else is in the same boat, please make sure you are checking your TFTP servers logs, and that it supports sub directories (some TFTP servers don't do directories).

cehjohnson 06-06-2007 02:09 AM

netboot with Windows tftpd
 
Quote:

Originally Posted by spudtheimpaler
I have given up on the netboot, fixed my cd drive, installed DSL and now have another coaster. Oh well, thanks to those who looked!

SpudTheImpaler - i wonder how you came to this? I'm desperately trying to avoid what you were going through ;-) (too many dependencies, too complex)

Personally i've come to this position due to CD problems - i have a SATA CD and the Etch installer seemingly can't deal with this.

Any advice for me now in hindsight on your postings?

Dutch Master 06-06-2007 02:12 AM

Use an IDE drive during installation or boot from the good-old floppydisk :)

spudtheimpaler 06-06-2007 07:44 AM

Quote:

Originally Posted by cehjohnson
SpudTheImpaler - i wonder how you came to this? I'm desperately trying to avoid what you were going through ;-) (too many dependencies, too complex)

Personally i've come to this position due to CD problems - i have a SATA CD and the Etch installer seemingly can't deal with this.

Any advice for me now in hindsight on your postings?

I would like to say that my perseverance and charm won the day, but alas no! Ripped a cd drive out of another machine and bob is your mothers brother. Sorry, I realise not what you want to hear, but i never sucessfully netbooted.

Good luck though, keep the thread posted on your progress!

IsaacKuo 06-06-2007 08:10 AM

I netboot with PXE on my LAN. I have it set up so that by default, the Debian 4.0 installer boots up. For MAC addresses of my various diskless workstations, they boot up to their various nfs root directories (they are all running Debian Etch installs).

There are a lot of "gotchas" involved. Once it's set up, though, it's a real pleasure. I don't have enough non-flakey optical drives to go around!

cehjohnson 06-07-2007 01:11 AM

Debian netboot tree wrong?
 
Quote:

Originally Posted by spudtheimpaler
Good luck though, keep the thread posted on your progress!


I suspect the Debian netboot.tar.gz is wrong. Anyhow, i used the structure of http://www.spic.net/u1/linux/dl/tftpboot.tar.bz2 from http://www.spic.net/u1/linux/netboot.html with the Debian files, but, with his 'default' file adapted and it worked.

The problem that caused me to netboot in the first place has now resurfaced part way through the Etch install though :-(

IsaacKuo 06-07-2007 09:30 AM

If I recall correctly, I didn't modify netboot.tar.gz in any fashion. I just extracted it to /tftpboot/ and it worked, IIRC.

cehjohnson 06-07-2007 10:13 AM

Windows/Linux
 
Isaac,

You may be right - that's why i was careful to express doubt about the tree's being wrong. Don't forget, i'm using a Windoze TFTP server though

IsaacKuo 06-07-2007 10:28 AM

Honestly I didn't even notice that you were using Windows tftpd. Reading your previous posts carefully, I notice you put that data in the subject line of your first post.

Sorry, I didn't even read your subject line. It seems my eyes simply don't even notice the subject lines of follow-up posts. I suspect I'm not alone in this...maybe it's a good idea to duplicate any subject line information in the body of a post. Maybe not even use subject lines for a followup post.


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