[linux-lvm] root fs on a LVM cause kernel panic

[linux-lvm] root fs on a LVM cause kernel panic

[Daniel Savard]

Hi everyone,

I am using LVM 1.0.1-rc4 and Linux 2.4.13.

I read the lvmcreate_initrd man page and followed the instructions to create
the kernel image with LVM support. However, I am unsuccessful to make it
working properly. The system boot and is showing its messages, including the
message about LVM support in the kernel and while it is trying to mount the
root filesystem, I am getting a kernel panic message saying the "root=" stanza
should be provided with a valid device for the root filesystem.

What am I doing wrong? Is there anything missing? Any way to get extra
debugging messages?


-- 

================================
Daniel Savard
CIDS Inc.
551, boul. Sir Wilfrid Laurier
suite 105
Beloeil, (Qu�bec)
Canada

J3G 4J1

T�l: (450) 467-8014
Internet: dsavard@videotron.ca
================================

Re: [linux-lvm] root fs on a LVM cause kernel panic

[Andreas Dilger]

On Nov 15, 2001  00:41 -0500, Daniel Savard wrote:
> I read the lvmcreate_initrd man page and followed the instructions to create
> the kernel image with LVM support. However, I am unsuccessful to make it
> working properly. The system boot and is showing its messages, including the
> message about LVM support in the kernel and while it is trying to mount the
> root filesystem, I am getting a kernel panic message saying the "root=" stanza
> should be provided with a valid device for the root filesystem.
> 
> What am I doing wrong? Is there anything missing? Any way to get extra
> debugging messages?

Did you add the initrd image to the kernel stanza in lilo.conf and re-run
lilo?  It sounds like your kernel is booting, but the VGs are not active.

Cheers, Andreas
--
Andreas Dilger
http://sourceforge.net/projects/ext2resize/
http://www-mddsp.enel.ucalgary.ca/People/adilger/

Re: [linux-lvm] root fs on a LVM cause kernel panic

[Daniel Savard]

Yes I did.

The behavior is exactly as you stated. It seems the VGs are never detected and
then the device for the root filesystem remains invalid.

Is there anything I can do to check what is going wrong? I am new to the initrd
and its usage. I don't know how to work with this beast... I don't think it is
related to the lilo.conf. I saw a comment in the linux-lvm mailing list from Les
Hazelton Sat, 13 Jan 2001 01:11:05-0500, it is very similar to my problem.
However, no solution is described.

I looked at the lvmcreate_initrd script and found the actual libraries where
not included in the image, just the symlinks where taken. I modified the script
in order to include the actual libraries. It didn't work.

The exact message is as follow:

(snip)
VFS: Cannot open root device "3a01" or 3a:01
Please append a correct "root=" boot option
Kernel panic: VFS: Unable to mount root fs on 3a:01

Daniel Savard

Le jeu, 15 nov 2001, vous avez �crit :
> On Nov 15, 2001  00:41 -0500, Daniel Savard wrote:
> > I read the lvmcreate_initrd man page and followed the instructions to create
> > the kernel image with LVM support. However, I am unsuccessful to make it
> > working properly. The system boot and is showing its messages, including the
> > message about LVM support in the kernel and while it is trying to mount the
> > root filesystem, I am getting a kernel panic message saying the "root=" stanza
> > should be provided with a valid device for the root filesystem.
> > 
> > What am I doing wrong? Is there anything missing? Any way to get extra
> > debugging messages?
> 
> Did you add the initrd image to the kernel stanza in lilo.conf and re-run
> lilo?  It sounds like your kernel is booting, but the VGs are not active.
> 
> Cheers, Andreas
> --
> Andreas Dilger
> http://sourceforge.net/projects/ext2resize/
> http://www-mddsp.enel.ucalgary.ca/People/adilger/

RE: [linux-lvm] root fs on a LVM cause kernel panic

[Joost van der Locht]

Hello,

Be sure that you compiled the SCSI drivers into the kernel. Because when you
use lvmcreate_initrd script it doesn't load in any modules for it.

Joost van der Locht
Technisch Directeur

E*Cube BV
Toernooiveld 214 - 6525 EC Nijmegen
T: 024-3500437 - F: 024-3500613
http://www.e-cube.nl
e-mail: joost@e-cube.nl             ICQ UIN: 494145

> -----Oorspronkelijk bericht-----
> Van: linux-lvm-admin@sistina.com
> [mailto:linux-lvm-admin@sistina.com]Namens Daniel Savard
> Verzonden: donderdag 15 november 2001 20:31
> Aan: linux-lvm@sistina.com
> Onderwerp: Re: [linux-lvm] root fs on a LVM cause kernel panic
>
>
> Yes I did.
>
> The behavior is exactly as you stated. It seems the VGs are never
> detected and
> then the device for the root filesystem remains invalid.
>
> Is there anything I can do to check what is going wrong? I am new
> to the initrd
> and its usage. I don't know how to work with this beast... I
> don't think it is
> related to the lilo.conf. I saw a comment in the linux-lvm
> mailing list from Les
> Hazelton Sat, 13 Jan 2001 01:11:05-0500, it is very similar to my problem.
> However, no solution is described.
>
> I looked at the lvmcreate_initrd script and found the actual
> libraries where
> not included in the image, just the symlinks where taken. I
> modified the script
> in order to include the actual libraries. It didn't work.
>
> The exact message is as follow:
>
> (snip)
> VFS: Cannot open root device "3a01" or 3a:01
> Please append a correct "root=" boot option
> Kernel panic: VFS: Unable to mount root fs on 3a:01
>
> Daniel Savard
>
> Le jeu, 15 nov 2001, vous avez écrit :
> > On Nov 15, 2001  00:41 -0500, Daniel Savard wrote:
> > > I read the lvmcreate_initrd man page and followed the
> instructions to create
> > > the kernel image with LVM support. However, I am unsuccessful
> to make it
> > > working properly. The system boot and is showing its
> messages, including the
> > > message about LVM support in the kernel and while it is
> trying to mount the
> > > root filesystem, I am getting a kernel panic message saying
> the "root=" stanza
> > > should be provided with a valid device for the root filesystem.
> > >
> > > What am I doing wrong? Is there anything missing? Any way to get extra
> > > debugging messages?
> >
> > Did you add the initrd image to the kernel stanza in lilo.conf
> and re-run
> > lilo?  It sounds like your kernel is booting, but the VGs are
> not active.
> >
> > Cheers, Andreas
> > --
> > Andreas Dilger
> > http://sourceforge.net/projects/ext2resize/
> > http://www-mddsp.enel.ucalgary.ca/People/adilger/
>
> _______________________________________________
> linux-lvm mailing list
> linux-lvm@sistina.com
> http://lists.sistina.com/mailman/listinfo/linux-lvm
> read the LVM HOW-TO at http://www.sistina.com/lvm/Pages/howto.html
>

[linux-lvm] root fs on a LVM cause kernel panic

[Daniel Savard]

I did further testing. Still not working. However, to make things clear I will
detail my environment.

Hardware:
 IBM Netfinity 5000 with RAID
 3 hot-swap disks 9 GB each
 1 Iomega SCSI external 2GB JAZ drive
 1 SCSI tape drive

OS:
  Started from RedHat 7.0
  Kernel at 2.4.13
  Many upgrades to rpms
  gcc at 3.0.2
  glibc 2.2.4
  LVM support built-in
  JFS support built-in
  SCSI support built-in

LVM:
  1.0.1-rc4

JFS:
  1.0.8

I am building a Linux From Scratch (LFS) system. For this purpose, I have
created a VG (datavg). And a 1GB LV (lv_lfs). The LFS system has been built
sucessfully. The old system is RedHat 7.0, with root fs on a non LVM ext2
filesystem. I was able to create the LVM, the JFS filesystem and compile
everything in this file system accordingly to instructions for LFS 3.0. No
major modifications where required from LFS 3.0, except the latest versions of
packages were used.

So, I have a fully functionnal RedHat system on plain ext2 filesystems with LVM
and JFS. The root fs is non-LVM ext2.

I also have a LV which contains a new root fs which is a JFS filesystem. I also
tried with ext2 filesystem and it doesn't fix the problem.

Now, the problem is:

I want to boot with my LV JFS filesystem as root fs. I followed man page
instructions for lvmcreate_initrd and created the initrd file. I checked the
initrd and everything seems to be there.

After a chat discussion with roadrunner on the openprojects lvm channel. We
checked everything in the initrd, as well as the linuxrc file in it and it
seems ok.

While booting I am ending with a kernel panic message. The few last lines of
the boot message are as follow:

VFS: Cannot open root device "3a01" or 3a:01
Please append a correct "root=" boot option
Kernel panic: VFS: Unable to mount root fs on 3a:01

I was suggested to try the following in the linuxrc file:

I added the following line just before the /sbin/umount /proc line:

/bin/echo "3A:01" > /proc/sys/kernel/real-root-dev

The /bin/echo executable was added to the initrd. It didn't fix the problem.

My lilo.conf file is as follow:

image=/boot/lfskernel-2.4.13
        initrd = /boot/initrd-lvm-2.4.13.gz
        root = /dev/datavg/lv_lfs
        label = lvmjfs
        append = "ramdisk_size=8192"
        read-only

I also tested with ramdisk_size=X, where X is the size returned by the
lvmcreate_initrd script for the ramdisk.

Any help would be greatly appreciated.
-- 

================================
Daniel Savard
Internet: dsavard@videotron.ca
================================

Re: [linux-lvm] root fs on a LVM cause kernel panic

[Andreas Dilger]

On Nov 16, 2001  17:19 -0500, Daniel Savard wrote:
> While booting I am ending with a kernel panic message. The few last lines of
> the boot message are as follow:
> 
> VFS: Cannot open root device "3a01" or 3a:01
> Please append a correct "root=" boot option
> Kernel panic: VFS: Unable to mount root fs on 3a:01

Hmm, you only get that message when the initial boot is done, so two 
possibilities (I'm not an initrd guru, mind you):

1) you need to change the root= line in your lilo.conf to say "root=/dev/ram0"
   so that it will boot into the initrd.  Then do the real-root-dev trick
   (or try pivot_root if running a 2.4 kernel) after configuring the LVM
   stuff via vgscan; vgchange -a y.

2) You didn't re-run lilo after changing lilo.conf (yes, you probably did,
   but you can never tell from here, and always safe to ask).

> I also tested with ramdisk_size=X, where X is the size returned by the
> lvmcreate_initrd script for the ramdisk.

As long as this is larger than the size of the uncompressed ramdisk, you
should be OK.

Cheers, Andreas
--
Andreas Dilger
http://sourceforge.net/projects/ext2resize/
http://www-mddsp.enel.ucalgary.ca/People/adilger/

Re: [linux-lvm] root fs on a LVM cause kernel panic

[Daniel Savard]

Number 2 can be dropped. I re-ran lilo after changing the configuration.

I just tested number 1, this time I am getting an error while trying to access
/dev/ram0 which doesn't exist at this time in the execution sequence. 

The error message was as follow:

NET4: Unix domain sockets 1.0/SMP for Linux NET4.0
ds: no socket drivers loaded!
request_module [block-major-1]: Root fs not mounted
VFS: Cannot open root device "100" or 01:00
Please append a correct "root=" boot option
Kernel panic: VFS: Unable to mount root fs on 01:00

From this, I decided to check my kernel setup and discovered (silly me) I made
a newbie error. The initrd support at boot time was not enabled in my kernel.

So, thanks for help to everyone and particularily to roadrunner on the IRC
channel who give much time on-line to help me and Andreas Dilger.

My system is not fully functionnal yet, however, the LVM problem is solved.

My target configuration is a Linux From Scratch system, mostly based on V 3.0
instructions. But, instead of gcc 2.95.3 it is based on gcc 3.0.2 and glibc
2.2.4 with kernel 2.4.13. My remaining errors are with the initialization
scripts for the LFS, this is off topic on this dist list.

So, if I can help in the future with testing. Let me know.

 -- 

================================
Daniel Savard
Internet: dsavard@videotron.ca
================================

Le ven, 16 nov 2001, Andreas Dilger a �crit :
> On Nov 16, 2001  17:19 -0500, Daniel Savard wrote:
> > While booting I am ending with a kernel panic message. The few last lines of
> > the boot message are as follow:
> > 
> > VFS: Cannot open root device "3a01" or 3a:01
> > Please append a correct "root=" boot option
> > Kernel panic: VFS: Unable to mount root fs on 3a:01
> 
> Hmm, you only get that message when the initial boot is done, so two 
> possibilities (I'm not an initrd guru, mind you):
> 
> 1) you need to change the root= line in your lilo.conf to say "root=/dev/ram0"
>    so that it will boot into the initrd.  Then do the real-root-dev trick
>    (or try pivot_root if running a 2.4 kernel) after configuring the LVM
>    stuff via vgscan; vgchange -a y.
> 
> 2) You didn't re-run lilo after changing lilo.conf (yes, you probably did,
>    but you can never tell from here, and always safe to ask).
> 
> > I also tested with ramdisk_size=X, where X is the size returned by the
> > lvmcreate_initrd script for the ramdisk.
> 
> As long as this is larger than the size of the uncompressed ramdisk, you
> should be OK.
> 
> Cheers, Andreas
> --
> Andreas Dilger
> http://sourceforge.net/projects/ext2resize/
> http://www-mddsp.enel.ucalgary.ca/People/adilger/

RE: [linux-lvm] root fs on a LVM cause kernel panic

[Joost van der Locht]

Does Lilo support JFS? I use XFS instead of EXT2 but for that I needed to
patch lilo with XFS support.


Joost van der Locht
Technisch Directeur

E*Cube BV
Toernooiveld 214 - 6525 EC Nijmegen
T: 024-3500437 - F: 024-3500613
http://www.e-cube.nl
e-mail: joost@e-cube.nl             ICQ UIN: 494145

> -----Oorspronkelijk bericht-----
> Van: linux-lvm-admin@sistina.com
> [mailto:linux-lvm-admin@sistina.com]Namens Daniel Savard
> Verzonden: zaterdag 17 november 2001 5:10
> Aan: Andreas Dilger
> CC: linux-lvm@sistina.com
> Onderwerp: Re: [linux-lvm] root fs on a LVM cause kernel panic
>
>
> Number 2 can be dropped. I re-ran lilo after changing the configuration.
>
> I just tested number 1, this time I am getting an error while
> trying to access
> /dev/ram0 which doesn't exist at this time in the execution sequence.
>
> The error message was as follow:
>
> NET4: Unix domain sockets 1.0/SMP for Linux NET4.0
> ds: no socket drivers loaded!
> request_module [block-major-1]: Root fs not mounted
> VFS: Cannot open root device "100" or 01:00
> Please append a correct "root=" boot option
> Kernel panic: VFS: Unable to mount root fs on 01:00
>
> >From this, I decided to check my kernel setup and discovered
> (silly me) I made
> a newbie error. The initrd support at boot time was not enabled
> in my kernel.
>
> So, thanks for help to everyone and particularily to roadrunner on the IRC
> channel who give much time on-line to help me and Andreas Dilger.
>
> My system is not fully functionnal yet, however, the LVM problem
> is solved.
>
> My target configuration is a Linux From Scratch system, mostly
> based on V 3.0
> instructions. But, instead of gcc 2.95.3 it is based on gcc 3.0.2
> and glibc
> 2.2.4 with kernel 2.4.13. My remaining errors are with the initialization
> scripts for the LFS, this is off topic on this dist list.
>
> So, if I can help in the future with testing. Let me know.
>
>  --
>
> ================================
> Daniel Savard
> Internet: dsavard@videotron.ca
> ================================
>
> Le ven, 16 nov 2001, Andreas Dilger a écrit :
> > On Nov 16, 2001  17:19 -0500, Daniel Savard wrote:
> > > While booting I am ending with a kernel panic message. The
> few last lines of
> > > the boot message are as follow:
> > >
> > > VFS: Cannot open root device "3a01" or 3a:01
> > > Please append a correct "root=" boot option
> > > Kernel panic: VFS: Unable to mount root fs on 3a:01
> >
> > Hmm, you only get that message when the initial boot is done, so two
> > possibilities (I'm not an initrd guru, mind you):
> >
> > 1) you need to change the root= line in your lilo.conf to say
> "root=/dev/ram0"
> >    so that it will boot into the initrd.  Then do the
> real-root-dev trick
> >    (or try pivot_root if running a 2.4 kernel) after configuring the LVM
> >    stuff via vgscan; vgchange -a y.
> >
> > 2) You didn't re-run lilo after changing lilo.conf (yes, you
> probably did,
> >    but you can never tell from here, and always safe to ask).
> >
> > > I also tested with ramdisk_size=X, where X is the size returned by the
> > > lvmcreate_initrd script for the ramdisk.
> >
> > As long as this is larger than the size of the uncompressed ramdisk, you
> > should be OK.
> >
> > Cheers, Andreas
> > --
> > Andreas Dilger
> > http://sourceforge.net/projects/ext2resize/
> > http://www-mddsp.enel.ucalgary.ca/People/adilger/
>
>
> _______________________________________________
> linux-lvm mailing list
> linux-lvm@sistina.com
> http://lists.sistina.com/mailman/listinfo/linux-lvm
> read the LVM HOW-TO at http://www.sistina.com/lvm/Pages/howto.html
>

Re: [linux-lvm] root fs on a LVM cause kernel panic

[Brent Harding]

I used the size before the initrd line, before, had the same issue.
Regarding lfs, what's the difference of 3.0, and the 1027 CVS version, plus
the 11-6 new one, can't get the book for 1027 CVS which I've completed
downloading from ftp last night. Is there any easy way to boot this thing
up if I have no separate partition?
At 05:19 PM 11/16/01 -0500, you wrote:
>I did further testing. Still not working. However, to make things clear I
will
>detail my environment.
>
>Hardware:
> IBM Netfinity 5000 with RAID
> 3 hot-swap disks 9 GB each
> 1 Iomega SCSI external 2GB JAZ drive
> 1 SCSI tape drive
>
>OS:
>  Started from RedHat 7.0
>  Kernel at 2.4.13
>  Many upgrades to rpms
>  gcc at 3.0.2
>  glibc 2.2.4
>  LVM support built-in
>  JFS support built-in
>  SCSI support built-in
>
>LVM:
>  1.0.1-rc4
>
>JFS:
>  1.0.8
>
>I am building a Linux From Scratch (LFS) system. For this purpose, I have
>created a VG (datavg). And a 1GB LV (lv_lfs). The LFS system has been built
>sucessfully. The old system is RedHat 7.0, with root fs on a non LVM ext2
>filesystem. I was able to create the LVM, the JFS filesystem and compile
>everything in this file system accordingly to instructions for LFS 3.0. No
>major modifications where required from LFS 3.0, except the latest
versions of
>packages were used.
>
>So, I have a fully functionnal RedHat system on plain ext2 filesystems
with LVM
>and JFS. The root fs is non-LVM ext2.
>
>I also have a LV which contains a new root fs which is a JFS filesystem. I
also
>tried with ext2 filesystem and it doesn't fix the problem.
>
>Now, the problem is:
>
>I want to boot with my LV JFS filesystem as root fs. I followed man page
>instructions for lvmcreate_initrd and created the initrd file. I checked the
>initrd and everything seems to be there.
>
>After a chat discussion with roadrunner on the openprojects lvm channel. We
>checked everything in the initrd, as well as the linuxrc file in it and it
>seems ok.
>
>While booting I am ending with a kernel panic message. The few last lines of
>the boot message are as follow:
>
>VFS: Cannot open root device "3a01" or 3a:01
>Please append a correct "root=" boot option
>Kernel panic: VFS: Unable to mount root fs on 3a:01
>
>I was suggested to try the following in the linuxrc file:
>
>I added the following line just before the /sbin/umount /proc line:
>
>/bin/echo "3A:01" > /proc/sys/kernel/real-root-dev
>
>The /bin/echo executable was added to the initrd. It didn't fix the problem.
>
>My lilo.conf file is as follow:
>
>image=/boot/lfskernel-2.4.13
>        initrd = /boot/initrd-lvm-2.4.13.gz
>        root = /dev/datavg/lv_lfs
>        label = lvmjfs
>        append = "ramdisk_size=8192"
>        read-only
>
>I also tested with ramdisk_size=X, where X is the size returned by the
>lvmcreate_initrd script for the ramdisk.
>
>Any help would be greatly appreciated.
>-- 
>
>================================
>Daniel Savard
>Internet: dsavard@videotron.ca
>================================
>
>
>_______________________________________________
>linux-lvm mailing list
>linux-lvm@sistina.com
>http://lists.sistina.com/mailman/listinfo/linux-lvm
>read the LVM HOW-TO at http://www.sistina.com/lvm/Pages/howto.html
>
>

[linux-lvm] root fs on a LVM cause kernel panic

[Daniel Savard]

No, the /boot is on a ext2 filesystem and JFS is built-in the kernel. I
followed the instructions from the IBM web site for JFS. However, I am not
finished with my setup and I cannot confirm you if it is working as expected.
But, the procedure makes sense.

> Does Lilo support JFS? I use XFS instead of EXT2 but for that I needed to
> patch lilo with XFS support.
>
>
> Joost van der Locht
> Technisch Directeur

-- 

================================
Daniel Savard
Internet: dsavard@videotron.ca
================================