I needed to clone a hard drive, so I bought the exact same model that I have and stuck it into the computer. I put Ubuntu live on a flash drive and boot up from it. I check with sudo fdisk -l that I really want to clone sda to sdb. Then I type
sudo dd if=/dev/sda of=/dev/sdb bs=1M
and press enter. This is first time I do it. I knew there's no progress bar or anything but I expected hard drives to at least make some noise to let me know they went on cloning.
Nothing. After about 10 minutes screen goes dark, I wiggle the mouse around and it's back. Later it goes dark again. This time neither moving mouse around nor hitting space bar help. The screen is dark.
Any way to bring it back? If I restart Ubuntu while dd-ing, would this damage either of hard drives? I've googled this and has only found that Ubuntu live doesn't have a standby mode. Pretty confusing.