today I installed Ubuntu 64-bit on a netbook. When the netbook boots this, error report appeared. I think there is a problem with the partitions.
Gave up waiting for root device. Common problems:
— Boot args (cat /proc/cmdline)
— Check rootdelay= (did the system wait long enough?)
— Check root= (did the system wait for the right device?)
— Missing modules (cat /proc/modules; ls /dev)
ALERT! /dev/mapper/ubuntu--vg-root does not exist. Dropping to a shell!
BusyBox v.1.21.1 (Ubuntu 1:1.21.1-1ubuntu1) built-in shell (ash)
Enter 'help' for list of built-in commands.
(initramfs)
Output of lsblk as requested:
$ lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 232.9G 0 disk
├─sda1 8:1 0 231G 0 part
├─sda2 8:2 0 1K 0 part
└─sda5 8:5 0 2G 0 part [SWAP]
sr0 11:0 1 1.2G 0 rom /cdrom
loop0 7:0 0 1.1G 1 loop /rofs
Best Answer
Please add the outputs of lsblk -fs, fdisk /dev/sda with p flag and the report of grub repair to the question as pastebin links.
Based on searching, there seems to be similar questions on Ask Ubuntu that has no answer up to date here and Here one answer is given which explains about raid and ubuntu.
There seems to be several suggestions, some of which seem to work for some people.
From the initframs prompt try typing
ls /dev/mapper
and see if your root volume is listed. If it is not listed, try waiting 10 seconds and run ls again.If it is now listed, type
exit
and it should now find the root device and boot (taken from hereEdit the boot config by pressing
e
when grub alert to choose OS, and replaceroot=UUID-6500...
byroot=/dev/sdx
where sdx is the boot partition. The problem here seems to be that the UUID is either wrong, or/dev/disk/by-UUID...
does not exist(1)all_generic_ide
to the end of the boot-line likekernel /boot/vmlinuz-2.6.27-7-generic root=UUID=43206294-74ef-434d-aca2-db74b4257590 ro quiet splash all_generic_ide
seems to work for some people (2)Recovery
option might work for some peopleThe error
/dev/mapper/ubuntu-vg-root
seems to be related to raid as described here."In the installer summary screen right before the copy process starts, click the Advanced button. Change the boot partition (this is the MSDOS-style "parent" partition not the Linux partitions) to /dev/mapper/pdc_feddabdf (or whatever dmraid lists as your fakeraid partition) Make sure the checkbox is clicked to boot from this disk. note that the installer will modify grub2 to point to the correct logical partition /dev/mapper/pdc_feddabdf1 or whatever / is on."
Detailed instructions regarding installation is given in the referred site. Please check there for more info on installation of grub.
chroot
seems to work for some people (suggested by cpttripzz here). Instruction regarding chroot is here. You can also refer to this question at Unix & Linux. More details can be found at Arch Wiki and Gentoo Wiki.