"L 01 01 01 01".

Can you help me... I have searched Net, but
nothing have found... What should I do?

Leszek

Sounds like the MBR was not copied.  You can issue a command like the
following to see if the MBR's are the same or not:

# dd if=/dev/hda bs=512 count=1 | hexdump -C

Of cousre you have to have a running linux system with both drives
available to do this.  

In short, you probably need to run lilo against Disk_B to update the MBR
for that disk.