Re: [Bug-ddrescue] Disc or partition?

[Ariel]

On Wed, 2 Aug 2006, David P James wrote:

> I inserted the disk into a linux box (as hdb) along with the new disk
> (as hdc). The new disk is at this point still unpartionned. Fdisk
> cannot read the partition table of the failed disk.
>
> To use ddrescue, should I attempt to copy the contents of the entire
> disk over to the new, unpartionned disk:
>
> ddrescue [options] /dev/hdb /dev/hdc rescue.log
>
> or should the new disk be partionned first and the drives of the failed
> disk copied over one by one?:
>
> ddrescue [options] /dev/hdb1 /dev/hdc1 rescue_c.log
> ddrescue [options] /dev/hdb5 /dev/hdc5 rescue_d.log

You wrote that fdisk can't read the partition table, yet you mention hdb1 
and hdb5?

If you CAN read the partition table, at least enough to have linux find 
them, then copy to two separate partitions on hdc. Having two of them will 
make it easier.

However, if linux can't read the partition table of hdb, then you have no 
choice, but to copy the entire disk. Then later run a tool that will 
attempt to rescue your partition, by searching the disk for 'start of 
filesystem'.

If the problem is that, linux can read the partition, but fdisk refuses to 
show it to you, just cat /prod/partitions, and find the size column.

On your new hard disk make the two new partitions the same size in as 
measured in sectors.

        -Ariel

PS. If linux is reading the partition table, but you suspect it's wrong
then don't trust it.