I have in the last two hours had two power failures and lost my posts just as I was to send. I have the feeling I need to read more about dd before I feel confident to carry out a clone. However if you would like to give me specific instructions based on following I will consider.
/dev/sdc1 - the first partition on an external USB hardrive
/dev/sdb5 - likely destination on internal 500 GB drive with NTFS front end.
From this linkhttp://www.linuxquestions.org/linux/answers/Applications_GUI_Multimedia/How_To_Do_Eveything_With_DD
Copy one hard disk partition to another hard disk:
dd if=/dev/sdc1 of=/dev/sdb5 bs=4096 conv=notrunc,noerror (edited by me)
notrunc means to not truncate.
noerror means to keep going if there is an error. Normally dd stops at any error.
sda2, sdb2 are partitions. You want to copy sda2 to sdb2. If sdb2 doesn't exist, dd will start at the beginning of the disk, and create it. Be careful with order of if and of. You can write a blank disk to a good disk if you get confused.
The two things you need to be careful of here is that you create the copy partition before starting, else it appears that the dd command will start at the beginning of the copy disk. (I have no experience of that happening ..... )
The copy partition must be capable of holding all that is in the original partition, so make sure it is of a suitable size.
The second thing is of course to ensure that you use if=
for the original and of=
for the copy. If you get them reversed you will wipe everything on the original.
Further I would suggest that when preparing the copy partition you should write zeros to it completely ..... that should ensure that any old data on the copy does not interfere with any recovery process later.
After cloning the partition, you should be able to securely wipe all files you do not want recovered ....... by writing zeros to them.
The copy partition should then only have the file info which was not overwritten.
IIRC the dd command will do all of this without having any of the partitions mounted.
If you do need to mount the original partition for any reason then please ensure it is mounted Read-Only. This is easily arranged in Linux, I have no idea about running Windows with that disk attached.
I would advise that this recovery is not done on partitions of a disk from which the OS is running.
It would be much better to have source and destination separate from the running OS.
I am unsure what you were saying about the " o " option .......... that wipes the partition table completely and writes a new clean, empty partition table to the disk.
I presume you did not use it.
Note: Power cuts are not conducive to recovery success .......
Repeating myself but ........ the disk with the data you wish to recover should be withdrawn from the PC, and when you are certain you are booting the OS OK, have the location for the copy set up - cleaned, then it can be re-attached in a position from which it will not boot or be mounted. The less chance of anything interfering with that disk the better chance you have of a successful recovery.
I cannot emphasise enough ...... never ever make even the slightest change to a disk from which you wish to recover data. Just clone the parts you need ...... several times if necessary ..... and make changes or whatever to the clone. Preserve the original at all costs.
I prefer to use a USB cradle for such devices ...... even though they are slower, I am more certain about the device node and can easily check to be sure.
Slow and certain is the only way.
Prepare well before starting.
Write out the commands you will use - in a text file - and double check them, so that you can copy and pasted them when required.
Be prepared to make changes if you find that your disks have been allocated different device nodes than you were expecting.