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Re: [LUG] grub error 25

 

On 06/12/11 21:27, Tony Sumner wrote:
> I proceeded with caution and disconnected /dev/sdb while I set about
> getting a system that would run. I cleared a partition on /dev/sda,
> installed Ubuntu 10.10 from a disk I had and got evelution running so
> that now I can write from here and I've unsubscribed Pat. I attached an
> external drive, plugged in /dev/sdb (now known as /dev/sdc) and 
> ran   
>   dd if=/dev/sdc of=/dev/sdb6/newfile bs=512
> so I now have a 60GB file containing a copy of the original errant
> drive. I understand that vi will edit a binary file.
>
> I also ran fdisk on the original drive and got this:
>
>    Device Boot      Start         End      Blocks   Id  System
> /dev/sdb1   *           1        3000    24097468+  83  Linux
> /dev/sdb2            3001        3122      979965   83  Linux
> /dev/sdb3            3123        3244      979965   82  Linux swap  
> /dev/sdb4            3245       14593    91160842+  83  Linux
>
> which looks ok. I am still trying to find out about smarctl. 
>
> About Knoppix: I heard tell that it was thought to be a good live OS for
> rescue purposes and that is the only reason I chose it. I'll have look
> at supergrub and drml when I can.
>
> About reiserfs: same thing really. When I was building this system I got
> two huge, as I thought at the time (2TB was not around), disks and
> reiserfs was said to be good for lots of files. If I can recover some
> information from this mess I am quite happy with ext3. 
>
> So where do I go from here? What is the next step? 
>
> Tony

There are many, many ways to proceed from here: start by reading this
handy guide.

http://tinyapps.org/docs/mount_partitions_from_disk_images.html

Using kpartx will be the safest and easiest method for you to get
started without having to specify offsets, etc. Don't forget to install
all the relevant reiserfs tools and so on first so you can actually read
out the filesystem contents once you have mounted the partitions from
the image file. Good luck, and of course feel free to ask any more
questions.

Forget knoppix and reiserfs, they're both also-rans of the linux world
these days - nothing wrong with knoppix per se, just nothing
particularly in it's favour any more either. DO forget reiserfs
completely though, that horse has bolted and it no longer has a place in
any sane person's workflow.

"sudo smartctl -A /dev/sdX" is the command you want to review the
smartctl data from sdX, the problem is learning how to read the output.

"sudo smartctl --test=short /dev/sdX" and "sudo smartctl --test=long
/dev/sdX" will do exactly what you imagine, the long test can take many
hours to execute however and can sometimes be the final straw for a very
ill unit.

Cheers,

Mat

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