Hi,

When I started up my pc today I noticed a message stating "error: unknown filesystem." with a prompt "grub rescue>"
I knew my hd had already some errors on it, but never tried to fix it since I didn't want to break it because everything worked fine.

I have two questions:
1) what can I do get my pc started up again? I assume I could try to re-install grub manager but how do I do this (I'm linux-newbie you know).
2)What are the possible dangers given my hd is not in perfect shape (but not that bad neither, no read errors, no crashes..., gparted stated that my hd had errors, that's all i know)

thanx!

ps: with live session i'm able to read and write to harddisk.

Assuming that you are using 9.10 or later reinstall using these instructions:

https://help.ubuntu.com/community/Gr...0from%20LiveCD

I would follow these instructions as a first attempt to fix this problem;

https://help.ubuntu.com/community/Grub2

Ignore any instructions about editing files. All you should need is the "sudo grub-install" command. "sudo update-grub" needs to be run when you are back on your OS.

If that does not work follow these instructions;
https://help.ubuntu.com/community/Gr...0Rescue%20Mode

You may want to look at the second one first and if it does not scare you off use it first.

I've tried both methods, but when using the command

"sudo mount /dev/sd06 /mnt/home" I receive the message "specify file system"

What else parameters do I have to give in for this command to work?

when trieng the ubuntu gui method, the only partition I cannot see is the partition on which kubuntu 10.10 is installed, my home and swap partitions as well as the windows partition i can see.


thx in advance

What is this? You probably should be selecting /dev/sda6 not /dev/sd06

Use
to check if you are not sure.

my apologies,

I noted it wrong in the previous post.

What I did was:


"sudo mount /dev/sda6 /mnt/home" (after first creating the directory /mnt/home)

the output i get is:

"mount: you pust specify the filesystem type"

what should i type?

thanx,

Wouter

update:

I tried sudo mount -t ext4 /dev/sda6 /mnt/home
and got:

wrong fs type, bad option, bad superblock on /dev/sda6,
missing codepage or helper program, or other error
In some cases useful info is found in syslog - try
dmesg | tail or so

when doing dmesg, i receive:
[ 61.994042] ppdev: user-space parallel port driver
[ 66.959230] EMU10K1_Audigy 0000:04:05.0: PCI INT A -> GSI 20 (level, low) -> IRQ 20
[ 69.250186] ADDRCONF(NETDEV_UP): eth0: link is not ready
[ 72.240383] uli526x: eth0 NIC Link is Up 100 Mbps Full duplex
[ 72.240633] ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
[ 75.962198] lp0: using parport0 (interrupt-driven).
[ 83.109650] eth0: no IPv6 routers present
[ 145.613874] CPUFREQ: Per core ondemand sysfs interface is deprecated - up_threshold
[ 148.630030] Clocksource tsc unstable (delta = -105215404 ns)
[ 856.582306] EXT4-fs (sda6): VFS: Can't find ext4 filesystem

so whats wrong?

thanx

Basically what's wrong can be summed up in thisThe filesystem is broken - it may have been fixable previously, but may not be now. Try and run a fsck against it from a liveCD environment. May need to use a backup superblock - post back if you need that info.
What does your fstab specify ?.

Hi,

To be honnest, I don't know wat you mean by fsck nor fstab.

Could you be more precise what command I need to type, including the parameters?

thanx,

If you have a working Linux system, a simple "cat /etc/fstab" will show you that. From a liveCD you'll need to find it; look under "Places" for the appropriate "xx Gig Filesystem" (xx is the size; hopefully you won't have too many).
Whilst in the terminal enter these (be patient if using a liveCD and post the outputfsck is used to check (and repair) a filesystem - it can be destructive. I usually wouldn't recommend you use it unless you have a good backup. It's as simple as "fsck.ext4 /dev/sda6". You may not have any option but to try it.

The problem is that I cannot find my linux system partition when running a live session, only partitions i can see are the windows and home partitions (and also the swap I think). This is the main reason why i cannot use the suggestions previously mentioned.

I have two questions:

1)When doing fsck.ext4 /dev/sda, does this contain a risk for whole my hd or only for the mentioned partition (sda6, the linux system partition?)

2)Could a re-install of linux kubuntu 10.10 also solve my problems? (could it also take a risk for my windows partition?)

thx in advance

sonicboy

Simply put your Linux installation CD and boot it.

1.) There you will get a option called 'Install grub loader' and 'upgrade grub loader'
2.) Select 'Install grub loader'
3.) problem solved.

best regards,

Just that filesystem - you should be able to keep your home partition during the re-install if you choose to do that. Under "expert partitioner" or somesuch I imagine.
Your Windows stuff should be safe regardless.

Prodev, this is a filesystem error, not (strictly) a boot-loader issue. Just looks like it.

Update:

I re-installed kubuntu and it now i get grub screen again and kubuntu starts up. But the first boot i got a message "errors detected on /home, do you want to fix it, ignore, or don't mount partition" (or something similar, don't remember 100% exactly).

So, now everything works fine but I'm a little bit suspicious about getting similar problems again. What should I do to check my hd for errors and repair it (i presume with gparted?)

update 2:
I installed gparted and when viewing information on sda1 (my windows c: partition) i got the following warning

(first technical information, don't think it's necessary to type except for that it's an ntfs partition which is bootable)
error: this software has detechted that the disk has at least 3 bad sectors
warning: the disk has bad sector. This means physical damage on the disk surface caused by deterioration, manufacturing faults or other reason. The reliability of the disk ma stay stable or degrade fast. We suggest making a full backup urgently by running 'ntfsclone --rescue...' then run 'chkdsk /f /r' on windows and reboot it twice! Then you can resize NTFS safely by additionaly using the --bad-sectors option of ntfsresize.

unable to read the contents of this file system!
Because of this some operations may be unavailable

What should I do with this information? It's the same one I received when resizing my disk some months ago for installin linux (fyi: I resized the d: (sda2) partition so sda1 stayed intact). I'm a little bit affraid of destroying my whole disk while trying to repair it (noob indeed :-))
Also, I already tried to use chkdsk /f /r on windows, but i got a dialog stating the disk was in use and could be scanned when rebooting, I did this but since then i got the same message when booting windows (before the login screen). The disk is always in use and so windows cannot scan it. Has this something to do with the bad sectors?

Thanx for your information

syg00 thank you for notifying me