After some troubles with my desktop computer it’s going to be replaced with a new one. The desktop originally only had 1 disk, and that was going to be replaced as well, so I needed a backup. But I did not want to backup just my files, I wanted a total backup, so I could continue to work on the system, while I was wiping the original disk (don’t want mr dell to look at my private stuff).
So I bought myself a new disk, ofcourse it’s larger then the original, so I was not sure if a disk => disk copy would work. I found the program ddrescue, which did the job well. True, resuming windows after this caused a BSOD, but well, what else could you expect, the hardware changed while the system was “running”… After another reboot the system worked fine, as if nothing had changed. Resizing the disk was not possible, probably because of the dell restore partition behind the main ntfs partition, but well, it’s only temporary and I didn’t need the extra disk space in the first place. Copying a 250Gb disk took about 1 1/2 hours, not bad, IMHO.
After this doing a dd if=/dev/urandom of=/dev/MYOLDDISK took a way longer time. This is done with an average speed of 2.2Mb/sec, so the entire process of a 250Gb disk takes approximately 34 hours! At least, on my system. So if you need to wipe your data, take your time.
Perhaps I should have read the comments on the page with ddrescue, the copy speed could be faster if I used another tool. For example CloneZilla. ddrescue did the job for me, but there might be better alternatives for it available.