On Sat, 3 Aug 2013, Robert wrote:
While some disks emulate their 4k sectors as 512b, some don't. E.g., I have a WD "My Book 1140" 3TB external USB disk, which reports 4k. Softraid doesn't work with it, I have to use vnd instead (for encryption).
Some new WD My Book models alegedly allow you to select sector size (512 bytes or 4096 bytes) with WD Quick Formatter software. You must ``format'' the drive as Factory Default (as opposite to XP Compatible) for 512-byte blocks. I don't know what happens with the data already on the disk, though.
Be aware, that many recent WD My Book drives also silently encrypt everything on the disk with unique encryption key stored in the enclosure electronics. They encrypt data sectors *always*, you don't need to set a password. Once the enclosure electronics dies or you move the disk out of the enclosure, you won't get your data back.
I also believe that in case of your disk, data are stored as 4096-byte sectors on platters, drive electronics emulates 512-byte sectors (512e) on the SATA interface and the enclosure groups those 512-byte sectors back again to emulate 4096-byte sectors on the USB interface. So your disk likely emulates 512-byte sectors, while the enclosure emulates 4096-byte sectors, even if you had used a real 512-byte sector drive in it.
Regards, David
