Hi,Guys
I installed Xen3.0.2 on CentOS4.2 platform with xen-3.0.2-src.tgz or
xen-2.0.7-install-x86_32.tar,but I got below error during boot from Xen
kernel:
VFS: Cannot open root device "/" or unknown-block(0,0)
Please append a correct "root=" boot option
Kernel panic - not syncing: VFS: Unable to mount root fs on
unknown-block(0,0)
any idea for this issue,it is really appreciated!
More,grub.conf file :
default=0
timeout=5
splashimage=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
title CentOS-4 i386 (2.6.9-22.ELsmp)
root (hd0,0)
kernel /vmlinuz-2.6.9-22.ELsmp ro root=LABEL=/ rhgb quiet
initrd /initrd-2.6.9-22.ELsmp.img
title CentOS-4 i386-up (2.6.9-22.EL)
root (hd0,0)
kernel /vmlinuz-2.6.9-22.EL ro root=LABEL=/ rhgb quiet
initrd /initrd-2.6.9-22.EL.img
title Xen 3.0 / XenLinux 2.6
kernel /xen-3.0.gz console=vga
module /vmlinuz-2.6-xen root=LABEL=/ ro console=tty0
Regards
--Taylor
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Xen-users mailing list
Xen-users@lists.xensource.com
http://lists.xensource.com/xen-users
Hi, It seems, that your xen kernel is unhappy with just labels of partitions, try passing the real partition name, e.g root=/dev/sda3 Good luck Geza> Hi,Guys > > I installed Xen3.0.2 on CentOS4.2 platform with xen-3.0.2-src.tgz or > xen-2.0.7-install-x86_32.tar,but I got below error during boot from Xen > kernel: > > VFS: Cannot open root device "/" or unknown-block(0,0) > Please append a correct "root=" boot option > Kernel panic - not syncing: VFS: Unable to mount root fs on > unknown-block(0,0) > > any idea for this issue,it is really appreciated! > > More,grub.conf file : > > default=0 > timeout=5 > splashimage=(hd0,0)/grub/splash.xpm.gz > hiddenmenu > title CentOS-4 i386 (2.6.9-22.ELsmp) > root (hd0,0) > kernel /vmlinuz-2.6.9-22.ELsmp ro root=LABEL=/ rhgb quiet > initrd /initrd-2.6.9-22.ELsmp.img > title CentOS-4 i386-up (2.6.9-22.EL) > root (hd0,0) > kernel /vmlinuz-2.6.9-22.EL ro root=LABEL=/ rhgb quiet > initrd /initrd-2.6.9-22.EL.img > title Xen 3.0 / XenLinux 2.6 > kernel /xen-3.0.gz console=vga > module /vmlinuz-2.6-xen root=LABEL=/ ro console=tty0 > > Regards > > --Taylor > > > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xensource.com > http://lists.xensource.com/xen-users >_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Taylor Lee wrote:> Hi,Guys >Hello, Taylor Lee,> I installed Xen3.0.2 on CentOS4.2 platform with xen-3.0.2-src.tgz or > xen-2.0.7-install-x86_32.tar,but I got below error during boot from Xen > kernel: > > VFS: Cannot open root device "/" or unknown-block(0,0) > Please append a correct "root=" boot option > Kernel panic - not syncing: VFS: Unable to mount root fs on > unknown-block(0,0) > > any idea for this issue,it is really appreciated! > > More,grub.conf file : > > default=0 > timeout=5 > splashimage=(hd0,0)/grub/splash.xpm.gz > hiddenmenu > title CentOS-4 i386 (2.6.9-22.ELsmp) > root (hd0,0) > kernel /vmlinuz-2.6.9-22.ELsmp ro root=LABEL=/ rhgb quiet > initrd /initrd-2.6.9-22.ELsmp.img > title CentOS-4 i386-up (2.6.9-22.EL) > root (hd0,0) > kernel /vmlinuz-2.6.9-22.EL ro root=LABEL=/ rhgb quiet > initrd /initrd-2.6.9-22.EL.img > title Xen 3.0 / XenLinux 2.6 > kernel /xen-3.0.gz console=vga > module /vmlinuz-2.6-xen root=LABEL=/ ro console=tty0I think the problem is here. The other two boot invocations use an "initrd" but the Xen invocation doesn''t. Create one and add a line for it and you should be good to go. If you built your own xen kernel you will need to resolve its module dependencies first: depmod 2.6.16-xen Then, assuming you have no special devices or filesystems this should make an initrd: mkinitrd /boot/initrd-2.6.16-xen.img 2.6.16-xen Now add the following line to your grub Xen stanza: module /initrd-2.6.16-xen.img Hope that gets you going. Mike Wright> > Regards > > --Taylor > > > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xensource.com > http://lists.xensource.com/xen-users > >_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Hi all, I''m trying to compile my own Xen kernel and I''m now getting this same error:> VFS: Cannot open root device "/" or unknown-block(0,0) > Please append a correct "root=" boot option > Kernel panic - not syncing: VFS: Unable to mount root fs on > unknown-block(0,0)Only my kernel line says "root=/dev/sda2" - I''m positive I compiled in the driver for my SATA controller (it''s there in the .config, assuming I''m reading the right one) but it still won''t recognise it. I even changed it to root=/dev/hda assuming it would fail with an invalid filesystem, but it still says "unknown-block(0,0)". While I was trying to figure out how the kernel knows what "/dev/sda2" means I thought I could try creating an initrd image with the important /dev files in it, and while the kernel recognises and loads the initrd file, just after that it comes up with the same error again. Any ideas what could be causing this problem? ...Or how you''re otherwise supposed to tell the kernel where your root partition is? Thanks, Adam. _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
I had this problem with our SCSI drive when we configured the driver as a module. I did compile the SCSI module statically to the kernal and created initrd image using --builtin=<module name> option and was successful to load root partition. I had also to add fusion mtp support to the kernel statically. Adam Nielsen wrote:>Hi all, > >I''m trying to compile my own Xen kernel and I''m now getting this same >error: > > > >>VFS: Cannot open root device "/" or unknown-block(0,0) >>Please append a correct "root=" boot option >>Kernel panic - not syncing: VFS: Unable to mount root fs on >>unknown-block(0,0) >> >> > >Only my kernel line says "root=/dev/sda2" - I''m positive I compiled in >the driver for my SATA controller (it''s there in the .config, assuming >I''m reading the right one) but it still won''t recognise it. I even >changed it to root=/dev/hda assuming it would fail with an invalid >filesystem, but it still says "unknown-block(0,0)". > >While I was trying to figure out how the kernel knows what "/dev/sda2" >means I thought I could try creating an initrd image with the >important /dev files in it, and while the kernel recognises and loads >the initrd file, just after that it comes up with the same error again. > >Any ideas what could be causing this problem? ...Or how you''re >otherwise supposed to tell the kernel where your root partition is? > >Thanks, >Adam. > >_______________________________________________ >Xen-users mailing list >Xen-users@lists.xensource.com >http://lists.xensource.com/xen-users > > > >_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
I have had the same problem earlier. Just add the root=/dev/sda2 in your grub entry for xen kernel. This will help in booting up the machine. On 6/5/06, Adam Nielsen <adam.nielsen@uq.edu.au> wrote:> > Hi all, > > I''m trying to compile my own Xen kernel and I''m now getting this same > error: > > > VFS: Cannot open root device "/" or unknown-block(0,0) > > Please append a correct "root=" boot option > > Kernel panic - not syncing: VFS: Unable to mount root fs on > > unknown-block(0,0) > > Only my kernel line says "root=/dev/sda2" - I''m positive I compiled in > the driver for my SATA controller (it''s there in the .config, assuming > I''m reading the right one) but it still won''t recognise it. I even > changed it to root=/dev/hda assuming it would fail with an invalid > filesystem, but it still says "unknown-block(0,0)". > > While I was trying to figure out how the kernel knows what "/dev/sda2" > means I thought I could try creating an initrd image with the > important /dev files in it, and while the kernel recognises and loads > the initrd file, just after that it comes up with the same error again. > > Any ideas what could be causing this problem? ...Or how you''re > otherwise supposed to tell the kernel where your root partition is? > > Thanks, > Adam. > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xensource.com > http://lists.xensource.com/xen-users >-- regards, Anand Gupta _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
> I have had the same problem earlier. Just add the root=/dev/sda2 in > your grub entry for xen kernel. This will help in booting up the > machine.Sorry, I''m not sure what you mean - this is my grub config - the first one works, the second one doesn''t: title Linux-2.6.11-skas root (hd0,1) # /dev/sda2 kernel /boot/bzImage-2.6.11-skas root=/dev/sda2 title Xen 3.0 / XenLinux 2.6 (root=/dev/sda2) root (hd0,1) # /dev/sda2 kernel /boot/xen-3.0.gz dom0_mem=524288 module /boot/vmlinuz-2.6-xen0 root=/dev/sda2 ro console=tty0 Cheers, Adam. _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
> I had this problem with our SCSI drive when we configured the driver > as a module. I did compile the SCSI module statically to the kernal > and created initrd image using --builtin=<module name> option and was > successful to load root partition. I had also to add fusion mtp > support to the kernel statically.You mean you built the SCSI driver as part of the kernel, and then specified --builtin=<name> for your initrd? I will try that as soon as I can work out what the module name for my SATA controller is. I would''ve thought the kernel should know what drivers are already loaded though... Cheers, Adam. _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
As suggested earlier you may need to use an initrd image or confirm that you have compiled all needed modules to xen kernel statically. Are you sure you have compiled scsi module to kernel? By default it''s unlikely to be enabled in a xen kernel. Adam Nielsen wrote:>>I have had the same problem earlier. Just add the root=/dev/sda2 in >>your grub entry for xen kernel. This will help in booting up the >>machine. >> >> > >Sorry, I''m not sure what you mean - this is my grub config - the first >one works, the second one doesn''t: > >title Linux-2.6.11-skas > root (hd0,1) # /dev/sda2 > kernel /boot/bzImage-2.6.11-skas root=/dev/sda2 > >title Xen 3.0 / XenLinux 2.6 (root=/dev/sda2) > root (hd0,1) # /dev/sda2 > kernel /boot/xen-3.0.gz dom0_mem=524288 > module /boot/vmlinuz-2.6-xen0 root=/dev/sda2 ro console=tty0 > >Cheers, >Adam. > >_______________________________________________ >Xen-users mailing list >Xen-users@lists.xensource.com >http://lists.xensource.com/xen-users > > > >_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
> As suggested earlier you may need to use an initrd image or confirm > that you have compiled all needed modules to xen kernel statically. > Are you sure you have compiled scsi module to kernel? By default it''s > unlikely to be enabled in a xen kernel.Yep, it''s definitely compiled statically, which is why I can''t figure out what''s going wrong. I''ve never needed to use an initrd image before, I''ve always just compiled in everything I need to boot. Is mkinitrd supposed to automatically include any required modules? Because when I inspect the image it created, there are no modules at all, which means either I''m missing something completely, or all the important modules are being built statically and there''s no need to include any in the initrd image. Cheers, Adam. _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
> > As suggested earlier you may need to use an initrd image or confirm > > that you have compiled all needed modules to xen kernel statically. > > Are you sure you have compiled scsi module to kernel? By default > > it''s unlikely to be enabled in a xen kernel. > > Yep, it''s definitely compiled statically, which is why I can''t figure > out what''s going wrong. I''ve never needed to use an initrd image > before, I''ve always just compiled in everything I need to boot.Well it''s definitely compiled statically, because it detects the controller during boot well before it tries to mount the root filesystem. The odd thing is my normal (non-Xen) kernel flies through the SATA detection, but the Xen kernel detects the first SATA port and then sits there for a while (~20 seconds), and apparently never acknowledges there''s a disk there. So it looks like there''s an issue with the disk detection in there somewhere - either in Xen or in Linux 2.6.16.16. I''ll have a closer look tomorrow when I can get hold of a serial cable to monitor the boot messages more closely. Cheers, Adam. _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
I have the same sata hard drive for which i had to create initrd images. The reason why your second entry is not working is probably because of your sata drivers. Just run the mkinitrd to create a new initrd. I compiled my sata drivers statically in the kernel and then used --built-in=ata_piix with mkinitrd to specify that its already built in the kernel. The above helped me boot up the xen kernel, try it out and see if it works for you. On 6/5/06, Adam Nielsen <adam.nielsen@uq.edu.au> wrote:> > > I have had the same problem earlier. Just add the root=/dev/sda2 in > > your grub entry for xen kernel. This will help in booting up the > > machine. > > Sorry, I''m not sure what you mean - this is my grub config - the first > one works, the second one doesn''t: > > title Linux-2.6.11-skas > root (hd0,1) # /dev/sda2 > kernel /boot/bzImage-2.6.11-skas root=/dev/sda2 > > title Xen 3.0 / XenLinux 2.6 (root=/dev/sda2) > root (hd0,1) # /dev/sda2 > kernel /boot/xen-3.0.gz dom0_mem=524288 > module /boot/vmlinuz-2.6-xen0 root=/dev/sda2 ro console=tty0 > > Cheers, > Adam. >-- regards, Anand Gupta _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
> I have the same sata hard drive for which i had to create initrd > images. The reason why your second entry is not working is probably > because of your sata drivers. > > Just run the mkinitrd to create a new initrd. I compiled my sata > drivers statically in the kernel and then used --built-in=ata_piix > with mkinitrd to specify that its already built in the kernel.I just tried this, but unfortunately it didn''t make a difference (and ata_piix does appear to be the SATA driver for my Intel ICH6 SATA controller.) I''m not sure what --built-in actually does, but either way it doesn''t seem to make a difference. The statically-linked driver does load, and it does probe the SATA ports, but I don''t think it finds any disks - like I say I''ll have to set up a serial console because the messages whiz past so fast I can''t see whether it finds anything or not. Thanks for your suggestion though! Cheers, Adam. _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users