Arch Linux

avojevlavo

Member

Registered: 2010-05-27

Posts: 40

kernel panic -how to reinstall kernel from live cd?

following this guide https://wiki.archlinux.org/index.php/Kernel_Panics I downloaded and burned arch onto cd.

booted up from it, logged in as root.

I dont know how to mount

ls /dev/
block cdrom cdrw disk dvd0 dvdrw0 scd0 cd cdrom0 cdrw0 dvd dvdrw initctl sr0

mount /dev/scd0 /mnt
mount: you must specify the filesystem type

I dont remember my partitioning setup from first arch installation so how do I find out what kind of fs is there?
I remember that I had separate / /boot /home

I need those data, its important not to erase them, but right now I have no idea how to backup them.

please help anyone :)
thanks

a.

karol

Archivist

Registered: 2009-05-06

Posts: 25,440

Re: kernel panic -how to reinstall kernel from live cd?

Try 'fdisk -l'.
https://wiki.archlinux.org/index.php/Change_Root

Backup is a copy of your files, so you can use e.g.  rsync or dd or cp.

First, see what's up with that kernel and remember to always have up to date backups.

Last edited by karol (2011-04-18 13:10:31)

avojevlavo

Member

Registered: 2010-05-27

Posts: 40

Re: kernel panic -how to reinstall kernel from live cd?

as it seems there is this fdisk, so:

fdisk -l /dev/sr0
Note: sector size is 2048 (not 512)

Disk /dev/sr0: 691 MB ...
64 heads, 32 sectors/track ...
Units ...
Sector size ...
I/O size ...
Disk identifier: 0x74eaf53e

       Device Boot        Start        End       Blocks     Id       System
/dev/sr0p1      *             1           659       2699264   17      Hidden HPFS/NTFS

and when I do

fdisk -l /dev/scd0

will get me the same output

karol

Archivist

Registered: 2009-05-06

Posts: 25,440

Re: kernel panic -how to reinstall kernel from live cd?

What does 'fdisk -l' say? /dev/sr0 is your CD-ROM.

avojevlavo

Member

Registered: 2010-05-27

Posts: 40

Re: kernel panic -how to reinstall kernel from live cd?

fdisk -l

says nothing. is that bad?

hokasch

Member

Registered: 2007-09-23

Posts: 1,461

Re: kernel panic -how to reinstall kernel from live cd?

Did you run it as root?

edit: ah, live cd, so I ǵuess the answer is yes.

Last edited by hokasch (2011-04-18 14:21:40)

avojevlavo

Member

Registered: 2010-05-27

Posts: 40

Re: kernel panic -how to reinstall kernel from live cd?

bump,
what should I do with that fdisk now? ideas?

hcjl

Member

From: berlin

Registered: 2007-06-29

Posts: 330

Re: kernel panic -how to reinstall kernel from live cd?

testdisk & photorec shoud help > http://www.cgsecurity.org/wiki/TestDisk

try to rescue the data and then reinstall.

avojevlavo

Member

Registered: 2010-05-27

Posts: 40

Re: kernel panic -how to reinstall kernel from live cd?

is that really necessary? how could kernel panic screw with partitions?
because when I start my pc grub loads fine but then arch starts booting up and it gives me this

...
:: Running hook [v86d]
FATAL: Could not load /lib/modules/2.6.38-ARCH/modules.dep: no such file or directory
Waiting 10 seconds for device /dev/disk/by-uuid/ ... 
...
Root device '/dev/disk/by-uuid/ ... ' doesn't exist, Attempting to create it. 
ERROR: Unable to determine major/minor number of root device '/dev/disk/by-uuid/ .... '
You are being dropped to a recovery shell
 Type 'exit' to try continue booting
/bin/sh: can't access tty: job control turned off
[ramfs /]#

hcjl

Member

From: berlin

Registered: 2007-06-29

Posts: 330

Re: kernel panic -how to reinstall kernel from live cd?

so mbr seems to be ok, but fdisk cannot find any partition. somehow you have to find / restore your partitions. that's why testdisk should help.

Last edited by hcjl (2011-04-19 10:14:24)

avojevlavo

Member

Registered: 2010-05-27

Posts: 40

Re: kernel panic -how to reinstall kernel from live cd?

I have installed testdisk on another machine (win7) took the corrupted hdd from notebook and plugged it, started testdisk, selected hdd, selected intel/pc partition type, selected Analyse

now I see this

Disk /dev/sdb - 320 GB / 298 GiB - CHS 38913 255 63
Current partition structure:

     Partition                  Start         End         Size in sectors
 1 * Linux                      0 0  2     12 254 63      208844
 2 P Linux Swap                13 0  1    274 254 63     4209030
 3 P Linux                    275 0  1   2187 254 63    30732345
 4 P Linux                   2188 0  1  38912 254 63   589987125

what do I do now? how do I backup my data, apparently they are all there, I managed to browse my home folder with

P: List Files

and I do have enough space, so that is the first thing I would like to do before anything else.

EDIT: I managed to copy files to different hdd, but testdisk said that it Failed to copy some files. How do I find which files?

Last edited by avojevlavo (2011-04-24 19:28:50)