I'm trying to install Ubuntu. I don't know if it is important, but i'm trying to install it on external HDD. In the end i have external bootable HDD which only displays: error: file not found grub. Grub-install: error: efibootmgr failed to register the boot entry: Block device required. Subsequent apt commands (sudo apt autoremove) ended with the same error, as did sudo update-grub. /boot is not full.

I'm gettind this error at boot:

How to fix the UUID in Grub after restore from another machine? Ask Question 18. (and then run grub-install as root to permanently set the correct config). Boot from an Ubuntu USB stick, mount the ubuntu disk partition, chroot into it and then run grub-install. Reinstalling Grub - shows no volume groups found, how do you fix this? I'm attempting to install SliTaz on my old PC as dual-boot with XP. I ran it from liveCD and used the installer there. As far as I can tell, it installed fine (I can see the files on the partition), but Grub does not seem to have installed correctly.

Xvd device support with Gentoo running in Xen HVM guest. After patching the /sbin/grub-install to see xvd devices and modifying /boot/grub/device.map to be. No such file or directory Could not find device for /boot: Not found or not a block device The livecd sees the disks fine, and fdisk -l shows all my partitions: Disk /dev/xvda: 48.3.

grub error: disk 'lvid/caoMWu-o417-GMgh-6vFj-1qrw-iJMi-ypwm0f/Z2eotR-N0HN-nrol-3hUd-odMB-GzHy-4PrsnL' not found. Entering rescue mode..

I can't even get the GRUB menu, the error message show immediately up.

Now here's the situation: I had to replace my motherboard because it was broken, and just after the change (I've replaced with an identical one) I'm not able to boot anymore.

This is my setup:Archlinux distro, two hdd with a RAID1 and LVM builded on top of it.

Now I can't understand what happened, cause the UUID of the disk/partition should be remained the same even after mb replacement ?

What can I do/check to restore the system ?

Below some info about the LVM setup:

and the /etc/fstab :

2 Answers

Have you tried update-grub2?

Now I can't understand what happened, cause the UUID of the disk/partition should be remained the same even after mb replacement ?

But new mobo could ascribe hdds in a different way, so now it is not possible to start even GRUB.

It seems that your motherboard changed the UUIDs of your disks and lvs as is apt to happen.

When you go into recovery mode, you'll need to run one of the following commands:

ls -l /dev/disk/by-uuid

blkid

To find the UUID of your boot partition.

If necessary, you can run fdisk -l to help find out which is the boot partition.

You can then add the correct UUIDs to /etc/fstab and you will be able to boot again with no issues.

Nasir Riley

Mount Is Not A Block Device

Nasir Riley

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There are some trivial troubles that always obsess me.My Gentoo always complains 'Could not find the root block device in UUID=5f7c7e13-2a46-4ae4-a8c0-f77f84e80900' and stuck,once I try to boot. However, if I type the same device name /dev/sda2 in, the system goes on.I don´t know why. My Gentoo was installed in one partition /dev/sda2 and I mounted / into /dev/sda2.

I also have found some posts on the internet. Most posts say it is caused by kernel config,and compiling the corresponding fs as built-in into the kernel ,not as module can solve it.some says rootfs should be specified in grub after the kernel command, device name after root command in grub should be substituted by the UUID. I did it all, but those didn't work.

Here is my configuration in grub.

The Gentoo coexists with Ubuntu.

My /etc/fstab.

UUID of the corresponding name

Is there anyone has some ideas? thanks.

4 Answers

Finally, I figured it out after several days have gone.It is caused by driver problem. My Gentoo is installed in my external hard-disk connected with my laptop by a USB cable.However, the USB Mass Storage Support option wasn't masked build-in when I built my kernel.Hence, it always blocked in that way.If some are in the same boat with me, and you make sure you have compiled all the referenced file system as built-in, please check if the options as follows are built-in in your kernel.

• Device Driver-->USB Support -->USB Mass Storage Support
• Device Driver-->USB Support -->xHCI HCD (USB 3.0) support
• Device Driver-->USB Support --> EHCI HCD (USB 2.0) support

• Device Driver-->USB Support --> UHCI HCD (most Intel and VIA) support

• Device Driver-->USB Support --> Support for Host-side USB

If they don't, check it on.

Maybe it's the wrong hard drive in your grub.cfg

hd1,msdos2, ahci1,msdos2 etc. would refer to the second disk. Usually it's the first hd0,msdos1 having the grub installed on /dev/sda

check this with grub-install --recheck /dev/sda

Your partitions would look like this. (boot on primary)

To be honest I think the easiest way to do this is to just make a generic kernel.

I simply grab Ubuntu's kernel config, issue a make oldconfig and let genkernel --no-clean --menuconfig all do the rest.

• Emerge the kernel as Quick Install Guide tells you to.
• Grab the generic kernel config:
  1) Find the file you want. The most recent kernel version basically: http://kernel.ubuntu.com/~kernel-ppa/configs/
  2) wget -O /usr/src/linux/.config kernelconfigurl
• Run make oldconfig. Just hold 'Enter' if you don't know how to answer these. No, nothing bad will happen, it will default to the default answer, which is what you should pick in a generic kernel anyway.
• Run genkernel with genkernel --no-clean --menuconfig all. In the menu you can modify things if you wish, or you can just exit. And the install will commence.
• Generate your GRUB config with grub-mkconfig -o /boot/grub/grub.cfg

This kernel will contain almost all modules and whatnot. So everything you plug in will work. Some Unix veterans frown upon generic kernels. If you ran Ubuntu, Fedora, or basically any distribution whatsoever - you used generic kernels.

Do you want to make a minimal kernel without messing up?
No problem. After you boot this kernel, simply plug in all devices you will ever need. Once done, go into /usr/src/linux and issue make localmodconfig. Great, now you have a kernel with only the stuff you will need. Use genkernel to compile the new minimalistic version and install it the same way.

Grub-install /dev/sda Not Found Or Not A Block Device

Good luck.

Grub-install Not Found Or Not A Block Device

In my case, I boot a VMWare Fusion virtual machine with Gentoo. I had to set CONFIG_FUSION_SPI=Y.

Necktwi

Is Not A Block Device

Necktwi

Grub-install Could Not Find Device For /boot Not Found Or Not A Block Device

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