Encountered a problem and dropping me to a shell when boot LFS 7.7

glukosio · 09-04-2015, 05:55 AM

Hello everybody! After a couple of weeks of work I finally managed to (almost) boot my Linux from scratch distribution!
I built it on a USB drive. But when it's booting it arrives at:

Code:

The device /dev/sdb1, which is supposed to contain the root file system, does not exist.
Please fix this problem and exit this shell.

Encountered a problem!

Dropping you to a shell.

And then, after few lines it gives me the shell

Code:

sh-4.3#

in grub2 my config is:

Code:

set root=(hd1,1)
linux /boot/vmlinuz-3.19-lfs-7.7 root=/dev/sdb1 ro
initrd /boot/initrd.img-3.19.0

can anybody help me please?

Keith Hedger · 09-04-2015, 01:06 PM

dev numbers for usb disks can change from boot to boot use uuids instead, both in grub and fstab

glukosio · 09-04-2015, 01:11 PM

Quote:

Originally Posted by Keith Hedger

dev numbers for usb disks can change from boot to boot use uuids instead, both in grub and fstab

Thank you for the answer! I will try as soon as new kernel will complete building

glukosio · 09-04-2015, 01:54 PM

Nothing to do, tried with UUID, with PARTUUID, but nothing changes!

Head_on_a_Stick · 09-04-2015, 02:11 PM

You should post the modified grub.cfg (& fstab).

I think the problem may be that the root device is defined as "(hd1,1)" in grub.cfg

You could add a udev rule to consistently set the block device for your USB stick as /dev/sdb
https://wiki.archlinux.org/index.php...B_flash_device

glukosio · 09-04-2015, 03:40 PM

Quote:

Originally Posted by Head_on_a_Stick

You should post the modified grub.cfg (& fstab).

I think the problem may be that the root device is defined as "(hd1,1)" in grub.cfg

You could add a udev rule to consistently set the block device for your USB stick as /dev/sdb
https://wiki.archlinux.org/index.php...B_flash_device

Now I'll manage to do the udev rule.
The fact also is, that I didn't configurate grub on the usb partition, I'm using grub installed on the hard disk, so the usb is naturally (hd1,1). The problem is that I don't know from where should I take info about USB, from host system or from chrooted LFS environment?

glukosio · 09-04-2015, 04:45 PM

Quote:

Originally Posted by Keith Hedger

dev numbers for usb disks can change from boot to boot use uuids instead, both in grub and fstab

Here is my fstab from chrooted LFS:

Code:

root:/# cat /etc/fstab 
# Begin /etc/fstab

# file system mount-point type options dump fsck order
#

UUID=f7f897da-3c78-491c-a0ab-5554a0194158 / ext4 defaults 11
UUID=f1e28b2e-ed7c-43bc-ba73-b677079af5eb swap swap pri=1 0 0
proc /proc proc defaults 0 0
sysfs /sys sysfs defaults 0 0
devpts /dev/pts devpts gid=4,mode=620 0 0
shm /dev/shm tmpfs defaults 0 0

# End /etc/fstab

and here the grub.cfg (just the main debian boot and actual lfs setting):

Code:

menuentry 'Debian GNU/Linux' --class debian --class gnu-linux --class gnu --class os $menuentry_id_option 'gnulinux-simple-f2533710-1896-491b-a467-e042978a4d09' {
	load_video
	insmod gzio
	if [ x$grub_platform = xxen ]; then insmod xzio; insmod lzopio; fi
	insmod part_msdos
	insmod ext2
	set root='hd0,msdos1'
	if [ x$feature_platform_search_hint = xy ]; then
	  search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos1 --hint-efi=hd0,msdos1 --hint-baremetal=ahci0,msdos1 --hint='hd0,msdos1'  f2533710-1896-491b-a467-e042978a4d09
	else
	  search --no-floppy --fs-uuid --set=root f2533710-1896-491b-a467-e042978a4d09
	fi
	echo	'Caricamento Linux 3.11-2-amd64...'
	linux	/boot/vmlinuz-3.11-2-amd64 root=/dev/sda1 ro  quiet
	initrd  /boot/initrd.img-3.11-2-amd64

}
menuentry "GNU/Linux, Linux 3.19-lfs-7.7"{
	set root=(hd1,1)
	linux /boot/vmlinuz-3.19-lfs-7.7.1 root=UUID=f7f897da-3c78-491c-a0ab-5554a0194158 ro
	initrd /boot/initrd.img-3.19.0.1
}

Head_on_a_Stick · 09-04-2015, 04:58 PM

I don't think GRUB accepts "set root=UUID=$UUID"

glukosio · 09-04-2015, 05:00 PM

Quote:

Originally Posted by Head_on_a_Stick

I don't think GRUB accepts "set root=UUID=$UUID"

Yes, you're right, I've changed it after it gave me an error, but I didn't save.
Consider it (hd1,1), now I'll edit it

moonfrog · 09-04-2015, 08:02 PM

deleted by moonfrog

Head_on_a_Stick · 09-05-2015, 08:55 AM

Quote:

Originally Posted by moonfrog

There's an error in your grub entry

(hd1,1) points to sdb2

If rootfs is on sdb1 change it to (hd1,0)

This is incorrect.

In GRUB2, the drives are counted from zero but the partitions are counted from one.

http://www.gnu.org/software/grub/man...ing-convention

glukosio · 09-05-2015, 12:02 PM

Yes, it should be (hd1,1), it's the only one avaylable. (hd1) is not considered a bootable partition

moonfrog · 09-05-2015, 05:21 PM

Wow..now I'm giving false info

My apologies

I'll take my grey beard home

stoat · 09-15-2015, 09:53 PM

For booting a system on a USB drive, try the rootdelay kernel parameter to allow for the slower response time of the drive. Typically, people say rootdelay=10. I usually get by with rootdelay=5. Another thing to try is to build into the kernel the USB storage stuff such as Host-side USB, USB Mass Storage, EHCI HCD, possibly OHCI HCD or UHCI HCD.

glukosio · 09-16-2015, 04:18 AM

Quote:

Originally Posted by stoat

For booting a system on a USB drive, try the rootdelay kernel parameter to allow for the slower response time of the drive. Typically, people say rootdelay=10. I usually get by with rootdelay=5. Another thing to try is to build into the kernel the USB storage stuff such as Host-side USB, USB Mass Storage, EHCI HCD, possibly OHCI HCD or UHCI HCD.

Thank you so much, I'm trying to recompile the kernel now with the right USB stuff you said, EHCI and OHCI were set to module..
just rootdelay=10 didn't work, I'll let you know as soon as kernel will compile

ps. @moonfrog don't worry it may happen

EDIT: nothing to do