Advanced Format (AF) questions

[eoniverse]

Recently purchased some empty HDD enclosures (HGST Touro Desk Pro) that will only work in Advanced Format (AF) 4096-byte (4K) sector size. I have not used them yet.

Please excuse any incorrect terminology. I have no experience with AF HDD sectors and I am not technical ( so lay explanations would be appreciated).

The rest of my Win 7 pro system is using legacy sector size. I am on an x58 chipset. I have one boot drive and 4 internal storage drives using legacy sectors. What I would like to do is eventually copy the internal stored data onto these enclosures and use them as back ups in case my internal drives die. (I have no intention of backing up my boot drive this way. Just stored media/programs).

1. Am I able to copy/paste (not clone) data back and forth between AF and legacy HDD's?

2. Will the data being copied automatically use the HDD's new sector format and if I copy/paste in reverse will the data being copied from AF use the old legacy format on the internal HDD?

3. Does copy/paste between HDD's using these different formats create any HDD issues (performance, sector corruption, etc)?

4. If I were to take a legacy sector drive with data on it and insert it into one of these HDD enclosures I expect Windows 7 pro to want to format it. Is there a possible work around? (I doubt it but can't assume - so asking)

5. Thanks in advance for answers.

 

[fzabkar]

The HDD inside the enclosure will still be using 512e emulation mode, so it doesn't matter what kind of drive goes into the enclosure. It can be either AF or non-AF.

Instead it is the firmware on the small USB-SATA bridge board that does the 4KB-512e translation. The reason for this is that MBR partitions are limited to a capacity of 2TiB when the sector size is 512 bytes. That's because the limit is not a capacity limit per se, but a limit on the number of sectors that can be accommodated using 32 bits.

2^32 x 512 bytes = 2 terabytes

If the sector size is increased to 4KB, then the capacity limit for MBR partitions increases to 16TiB.

2^32 x 4096 bytes = 16 terabytes

Some manufacturers have taken this route in order to maintain compatibility will legacy OS-es such as Windows XP.

The drive and the bridge hardware constitute a USB mass storage device. Copying and pasting between an internal HDD and a USB mass storage device should be transparent to the OS ... as long as the HDD remains inside the enclosure. If you take the HDD, whether AF or non-AF, out of the enclosure and install it inside your PC, you will expose the HDD's native 512e sectors, rendering the data inaccessible. You will still see the partition table in sector 0, but every other sector will be out be a factor of 8. Remember, when the drive is initialised and formatted inside the enclosure, the file system consists of 4KB sectors. Inside the PC you will have a 512e drive with a 4KB file system. Obviously this isn't going to work.

 

[eoniverse]

Thanks for clearing that up.