Serious boot problem

[dennyg]

I've been trying to install the new 13.37 slackware on a new machine.
After installing to sda1 and formatting with fdisk or gdisk, on booting I
get "VFS: Cannot opoen root device "802" or unknown-block(8,2). I've
reinstalled several times, add root=/dev/sda1 etc, but nothing helps. I
don't have a boot disk obviously, since I can't run. Any help would be
appreciated.

[root]

Did you let the install disk do its own thing or did you tweak
anything? Did you install lilo to the MBR?

You can go back to the install disk and use it as a boot disk:
at the prompt, see the message "In a Pinch". You type
something like this:
hugesmp.s root=/dev/sda1 rdinit= ro

This will bypass lilo and should boot directly into sda1.

I have had troubles like this after building a new
kernel, but never after a new install.

[Kees Theunissen]

If that works check your /etc/lilo.conf.
Which kernel are you booting?
For now use one of the "huge" variants.
vmlinuz-huge-smp-2.6.37.6-smp is the kernel from the installation disk
and has been proven to work.

Also check your partition(s). Block device "(8,2)" or "802" from
the error-messages above is /dev/sda2 NOT /dev/sda1.

What hardware (diskdrive, chipset) do you have. Which filesystem did
you install as root filesystem? You might need to build an initrd
with additional drivers before you can boot a "generic" kernel.

Regards,

Kees.

--
Kees Theunissen.

[dennyg]

On Thu, 02 Feb 2012 17:09:00 +0000, root wrote:

> dennyg <denn...@cfl.rr.com> wrote:
>> I've been trying to install the new 13.37 slackware on a new machine.
>> After installing to sda1 and formatting with fdisk or gdisk, on booting I
>> get "VFS: Cannot opoen root device "802" or unknown-block(8,2). I've
>> reinstalled several times, add root=/dev/sda1 etc, but nothing helps. I
>> don't have a boot disk obviously, since I can't run. Any help would be
>> appreciated.
>
> Did you let the install disk do its own thing or did you tweak
> anything? Did you install lilo to the MBR?
>

> Yes.

You can go back to the install disk and use it as a boot disk:
> at the prompt, see the message "In a Pinch". You type
> something like this:
> hugesmp.s root=/dev/sda1 rdinit= ro
>
> This will bypass lilo and should boot directly into sda1.
>

Did that. Still no go.

> I have had troubles like this after building a new
> kernel, but never after a new install.

Been there, done that. Very carefully repeated everything including
rformating drive using gdisk. only now i get unknown=block 0,0. I'm
snowed. By the way, his isn't the first time I've loaded slackware on a
machine. Never had a problem like this. The only thing I've done
differently is use a SATA/USB external drive. But the software loads from
a cd just fine. Anybody have any ideas? Thanks in advance.

[Henrik Carlqvist]

dennyg <denn...@cfl.rr.com> wrote:
>>> I get "VFS: Cannot opoen root device "802" or unknown-block(8,2). I've
>>> reinstalled several times, add root=/dev/sda1 etc, but nothing helps.
>>> I don't have a boot disk obviously, since I can't run. Any help would
>>> be appreciated.

As Kees said, 8,2 is /dev/sda2. This does not mean that /dev/sda2 is the
right choice for you, it only means that you have tried /dev/sda2 and
failed. Did you mean to try anything else than sda2?

> The only thing I've done differently is use a SATA/USB external drive.
> But the software loads from a cd just fine. Anybody have any ideas?

Does your machine have any internal drives? If so /dev/sda is probably
assigned to an internal drive and for usb you should probably select
some other partition than sda*.

Before your kernel tries to mount your root file system, has it detected
all your disks? Does it correctly report all your partitions? Look for
messages looking something like this:

sd 3:0:0:0: [sda] 1465149168 512-byte logical blocks: (750 GB/698 GiB)
sd 3:0:0:0: [sda] Write Protect is off
sd 3:0:0:0: [sda] Mode Sense: 00 3a 00 00
sd 3:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO
or FUA
sda: sda1 sda2 sda3 < sda5 sda6 sda7 sda8 sda9 sda10 sda11 >
sd 3:0:0:0: [sda] Attached SCSI disk

regards Henrik
--
The address in the header is only to prevent spam. My real address is:
hc123(at)poolhem.se Examples of addresses which go to spammers:
root@localhost postmaster@localhost

[root]

dennyg <denn...@cfl.rr.com> wrote:
> On Thu, 02 Feb 2012 17:09:00 +0000, root wrote:
>
>> dennyg <denn...@cfl.rr.com> wrote:
>>> I've been trying to install the new 13.37 slackware on a new machine.
>>> After installing to sda1 and formatting with fdisk or gdisk, on booting I
>>> get "VFS: Cannot opoen root device "802" or unknown-block(8,2). I've
>>> reinstalled several times, add root=/dev/sda1 etc, but nothing helps. I
>>> don't have a boot disk obviously, since I can't run. Any help would be
>>> appreciated.
>>
>> Did you let the install disk do its own thing or did you tweak
>> anything? Did you install lilo to the MBR?
>>
>> Yes.
>
> You can go back to the install disk and use it as a boot disk:
>> at the prompt, see the message "In a Pinch". You type
>> something like this:
>> hugesmp.s root=/dev/sda1 rdinit= ro
>>
>> This will bypass lilo and should boot directly into sda1.
>>
> Did that. Still no go.
>

Boot back into the install disk, as if you were going
to do a new install. This time, however, do fdisk and
see what partitions are on the drive. Mount the partitions
and take a look at what is there. You may have a hardware
problem.

>
>> I have had troubles like this after building a new
>> kernel, but never after a new install.
>
> Been there, done that. Very carefully repeated everything including
> rformating drive using gdisk. only now i get unknown=block 0,0. I'm

When you say formatting, don't you really mean partitioning?

> snowed. By the way, his isn't the first time I've loaded slackware on a
> machine. Never had a problem like this. The only thing I've done
> differently is use a SATA/USB external drive. But the software loads from
> a cd just fine. Anybody have any ideas? Thanks in advance.

Is the drive so large that you need to partition with gdisk?

Is there anything else on the drive that matters to you?

If not, from the install disk, assuming the drive is /dev/sda
do:
dd if=/dev/null of=/dev/sda count=5000

start over by running fdisk, not gdisk, and partition the
drive as you want. Re-run fdisk to see that the partions
are there.

Then do setup and take defaults on everything. Let the
install do "everything".

Let it install lilo to the mbr.
Then reboot. If that fails I would bet the drive or
motherboard are bad.

[root]

Damn, I wasn't paying attention. Are you saying you want
the system to boot from a USB drive? You better check
that the bios can do that. Try hitting F8 when the
system is booting to pull up a boot menu. The failure
to boot an external drive has nothing to do with linux
or Slackware. That is a pure bios function.

[dennyg]

I have been playing games with the formating, so I have used somtimes one
and somtimes 2 partitions which accounts for the sda1/sda2 discrepancy.
That is the first one sometimes is my swap partition.

> What hardware (diskdrive, chipset) do you have. Which filesystem did you
> install as root filesystem? You might need to build an initrd with
> additional drivers before you can boot a "generic" kernel.

I'm using a 500 Gig western digital hd. As I said before it's a SATA/usb
external drive. I've also tried a 2T wd drive. Same thing there.And I use
the reiserfs. I did try my old v2.1 install disk and had the exact same
problem?????. The real funny thing was when I first loded the software I
only used the 1st install disk (cd) and it booted normally. When I loaded
the last 2 disks the problem started. I've tried repeating this
and now get the error. Boy, I'm stumped.>
> Regards,
>
> Kees.

Thanks for the quick response Kees. I haven't tried the huge kernal yet
but that's next.

[Sylvain Robitaille]

On Thu, 02 Feb 2012 11:30:00 -0500, dennyg wrote:

> I've been trying to install the new 13.37 slackware on a new machine.
> After installing to sda1 and formatting with fdisk or gdisk, on
> booting I get "VFS: Cannot opoen root device "802" or

> unknown-block(8,2). ...

Looks to me as though the kernel can't access the device which contains
your root filesystem. If you're using the "generic" kernel (as opposed
to "huge"), or a custom kernel, you likely need to create (or update, if
you already have one) the initrd that the kernel uses to load device
drivers from, with the appropriate driver(s) for your root disk device.

See "man mkinitrd" for details. I *think* the installer prompts to
create one, but if you're not on a regular hard disk, it might still
fail to install the necessary device driver(s). (I'm not sure how the
installer determines which device drivers to install, or whether it just
installs a canned set).

I hope I've helped.

--
----------------------------------------------------------------------
Sylvain Robitaille s...@encs.concordia.ca

Systems analyst / AITS Concordia University
Faculty of Engineering and Computer Science Montreal, Quebec, Canada
----------------------------------------------------------------------

[Helmut Hullen]

Hallo, dennyg,

Du meintest am 03.02.12:

>>>> I've been trying to install the new 13.37 slackware on a new
>>>> machine. After installing to sda1 and formatting with fdisk or
>>>> gdisk, on booting I get "VFS: Cannot opoen root device "802" or
>>>> unknown-block(8,2).

[...]

> I'm using a 500 Gig western digital hd. As I said before it's a
> SATA/usb external drive. I've also tried a 2T wd drive. Same thing
> there.

Has the machine also an internal disk?
I suppose this (possible) internal disk is "/dev/sda", and the USB
attached disk is "/dev/sdb".

But I haven't looked at the naming of USB attached disks which are used
for booting ...

Viele Gruesse
Helmut

"Ubuntu" - an African word, meaning "Slackware is too hard for me".

[Eef Hartman]

dennyg <denn...@cfl.rr.com> wrote:
> get "VFS: Cannot opoen root device "802" or unknown-block(8,2). I've
> reinstalled several times, add root=/dev/sda1 etc, but nothing helps. I

That mostly means either the DRIVER for the (probably S-ATA)
diskcontroller or the file system driver for the root fs is NOT in
the kernel you're booting. So the kernel cannot access its root.
Either supply a init-ramdisk with those drivers or rebuild the kernel
(through a live system) with those drivers included.
--
******************************************************************
** Eef Hartman, Delft University of Technology, dept. SSC/ICT **
** e-mail: E.J.M....@tudelft.nl - phone: +31-15-27 82525 **
******************************************************************

[Eef Hartman]

root <NoE...@home.org> wrote:
> system is booting to pull up a boot menu. The failure
> to boot an external drive has nothing to do with linux
> or Slackware. That is a pure bios function.

But the kernel MUST have the right USB drivers loaded (either
through the initrd or built-in) to access that USB-based root
fs after it has been loaded. They (the USB drivers) mostly are
modules, not built-in into the kernel, so you _will_ have to
load them from the initrd image.
Loading from the disk of course doesn't work as the kernel cannot
access that USB disk yet (chicken-and-egg problem).

[Markus]

On Fri, 03 Feb 2012 10:45:01 +0100, Eef Hartman
<E.J.M....@tudelft.nl> wrote:
> diskcontroller or the file system driver for the root fs is NOT in

Hi,

I think you should also make sure that the drivers for accessing an
USB-device are built into the kernel (or initrd) because it is an
external device.

Markus

--
Markus

[root]

Eef Hartman <E.J.M....@tudelft.nl> wrote:
> root <NoE...@home.org> wrote:
>> system is booting to pull up a boot menu. The failure
>> to boot an external drive has nothing to do with linux
>> or Slackware. That is a pure bios function.
>
> But the kernel MUST have the right USB drivers loaded (either
> through the initrd or built-in) to access that USB-based root
> fs after it has been loaded. They (the USB drivers) mostly are
> modules, not built-in into the kernel, so you _will_ have to
> load them from the initrd image.
> Loading from the disk of course doesn't work as the kernel cannot
> access that USB disk yet (chicken-and-egg problem).

The install disk always asks if we want to create a boot stick.
Wouldn't that also use one of the huge kernels?

I have never requested the boot stick.