2048 vs 4096 byte sectors on WD161KFGX

WD Internal Drives Internal Drives
1

Hello,

I recently bought a new WD161KFGX (WD Red Pro) 16TB drive. It has some strange sector size behavior. I’m using Linux.

Using hdparm, I can see the drive reports that it supports 512 and 2048 byte logical sectors:

$ sudo hdaprm -I /dev/sdg
ATA device, with non-removable media
        Model Number:       WDC WD161KFGX-68AFPN0
        Serial Number:      2BJW35NN
        Firmware Revision:  83.00A83
        ...
Configuration:
        ...
        Logical  Sector size:                   512 bytes [ Supported: 2048 256 ]
        Physical Sector size:                  4096 bytes
...

I want to use the drive with 4096 byte logical sectors, so I opened a support ticket. They reported that the disk does not support 4K logical sectors. So I got curious and enabled 2048 byte sectors.

Afterwards, the disk reports it’s using 4096 byte sectors even though it doesn’t support them:

$ sudo hdparm -I /dev/sdg
ATA device, with non-removable media
        Model Number:       WDC WD161KFGX-68AFPN0
        Serial Number:      2BJW35NN
        Firmware Revision:  83.00A83
        ...
Configuration:
        ...
        Logical  Sector size:                  4096 bytes [ Supported: 2048 256 ]
        Physical Sector size:                  4096 bytes
...

This is pretty weird: the drive switched to a different size than I requested, and it says thinks it doesn’t support that size.

Benchmarks are approximately expected, and I’m able to fill the drive without errors. So things seem to be working okay, but I’m concerned I’ve hit some firmware bugs - this doesn’t seem normal.

Anyone know anything?

Thanks,
Ross

2

Hi @rvandegrift,

Have you opened a Support Case? If not opened, for more information, please contact the WD Technical Support team for the best assistance and troubleshooting:
https://support-en.wd.com/app/ask

3

Yes, I did - they’re still looking into it. I thought I’d post here in case someone else noticed something similar.

4

Unfortunately, WD support told me that they would not help because I do not run Windows.