Grub Rescue Unknown Filesystem Error. Grub Corrupted or Filesystem?
- by nightcrawler
Now it has happened twice & have been pulling my hairs now...
I have installed xubuntu on my external hardisk & have been using it for about 3 months. It has three partitions, one of 500 mb mounted at /boot, 2nd one of 48gb mounted at / & the rest (out of 160gb) is ntfs partition....used as normal external storage. The last storage supposedly acts as a buffer b/w Linux distributions & Win platform, buffer in the sense that it provides a universal channel for data transfers.
I have constantly used this external hardisk for data transfers b/w win7 laptop & xubuntu (on this external hd) without any hassle. However, on of my desktops where I have ubuntu I (for the first time) attached this external drive which let me do data transfers where all three partitions properly mounted....but then nasty thing occurred the same that occurred before.
I (as usual) tried booting via this external hd (one having xubuntu, one having being formerly used under Ubuntu) I got error
Now I am totally devastated because similar thing happened ~6months before when I had fedora 17 in my external hd (instead of xubuntu) & after it was used under ubuntu the same happened...i didn't reported it because I already had planned towards debian instead of rpm!
The mystery is that as long as I don't attach this external hd under ubuntu the data never** corrupts whereas under win xp/7 I can use it as a normal usb storage of coarse linux partitions aren’t available under win platforms...
**From corrupts I mean hd fails to boot with the error mentioned however cant say whether data within remains untouched? It seems that my grub & or MBR is corrupted. Please sir guide me to solve this issue also why I cant attach & use linux external hds under linux platform
Disk /dev/sdc: 160.0 GB, 160041884672 bytes
255 heads, 63 sectors/track, 19457 cylinders, total 312581806 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x0004e7d0
Device Boot Start End Blocks Id System
/dev/sdc1 * 2048 976895 487424 83 Linux
/dev/sdc2 978942 96874495 47947777 5 Extended
/dev/sdc3 96874496 312575999 107850752 7 HPFS/NTFS/exFAT
/dev/sdc5 978944 94726143 46873600 83 Linux
/dev/sdc6 94728192 96874495 1073152 82 Linux swap / Solaris
I can recall for sure that have seen a thread here when a similar problem occurred & in response someone gave solution of how to mount (now invisible) partitions & recover important data in them. I have misplaced that URL so if any can guide me thither because my important documents resides in / partition
What I already have done:
Without success I have tried this & related solutions
What I plan to do:
I believe that filesystem has corrupted & would you recommend solution like this provided I cant recall whether my /boot (500mb) partition was ext4 or ext2 though I am sure that my / (48gb) partition was ext4
UPDATE 1
Attached my external hd under Ubuntu ran followinf command as root
grub-install /dev/sdc
where /dev/sdc was my external hd containing corrupted xubuntu....it reported all done! I re-ran fdisk -l but to my disappointment it reported
Disk /dev/sdc: 160.0 GB, 160041884672 bytes
255 heads, 63 sectors/track, 19457 cylinders, total 312581806 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x1b6b9167
Disk /dev/sdc doesn't contain a valid partition table
...& now I can't even access its ntfs partition (former /dev/sdc3) please help?
UPDATE 2
TestDisk (by cgsecurity) failed at founding any partition table :(
TestDisk 6.13, Data Recovery Utility, November 2011
Christophe GRENIER <[email protected]>
http://www.cgsecurity.org
Disk /dev/sdc - 160 GB / 149 GiB - CHS 19457 255 63
Partition Start End Size in sectors