Hi,

I was wondering if I could get some help with cloning hard disk.

I'd like to clone my old hard drive which is running on Ubuntu Server 10.04 so that I could set up an exact things on another machines.

I use the command "dd" to do the cloning.

example: $ dd if=/dev/sda6 of=/dev/sdb1

It finished the job with no errors but strangely there was nothing on the sdb1 (my external HD). And not only that, I could not un-mount the external hard disk. It said umount:/media/ExternalHD is not in the fstab (and you are not root).

I then went and run the command $ sudo chown user1:user1 /media/ExternalHD. This did not work either.

Any help would be greatly appreciated.

Thank you

Are the partitions exactly identical? If not, you can have a size issue when trying to clone from larger to smaller. If the disks are identical, an easier option is to just do

dd if=/dev/sda of=/dev/sdb

Try dumping out the full partition information on each disk with the following:

sfdisk -d /dev/sda
sfdisk -d /dev/sdb

Then compare the output to verify that /dev/sdb1 and /dev/sda6 are, in fact, identical. If they're not, you're playing with a whole world of other problems.

Thank you Xylos for your reply.

I think I might have cloned the wrong partition.

Here is the snapshot when I run the commands as instructed by you

# partition table of /dev/sda
unit: sectors

/dev/sda1 : start= 63, size=390636477, Id= 7, bootable
/dev/sda2 : start=390637566, size=234504194, Id= 5
/dev/sda3 : start= 0, size= 0, Id= 0
/dev/sda4 : start= 0, size= 0, Id= 0
/dev/sda5 : start=619139072, size= 6002688, Id=82
/dev/sda6 : start=390637568, size= 97654784, Id=83

# partition table of /dev/sdb
unit: sectors

/dev/sdb1 : start= 63, size=1953520002, Id= 7
/dev/sdb2 : start= 0, size= 0, Id= 0
/dev/sdb3 : start= 0, size= 0, Id= 0
/dev/sdb4 : start= 0, size= 0, Id= 0

What happens is I have two operating systems (Windows XP and Ubuntu) installed on this machine. And what I'd like to clone only is the Ubuntu OS partition.

I am just having a guess here - could it be /dev/sda1 for the ubuntu OS

The external HD (1TB) or sdb1 should be much bigger to accommodate the clone.

Thank you