I've bought a new 4TB hard drive, a Western Digital WD40PURX, to replace an existing 1TB drive, and because I don't have a free internal SATA port - I've used a USB-to-SATA adapter I had lying around to connect the drive temporarily so I can move the data over - before switching the drives.

But when I'm trying to partition the drive, Ubuntu only sees 1.6 TB of size:

# gdisk -l /dev/sdg
GPT fdisk (gdisk) version 1.0.1

Partition table scan:
  MBR: not present
  BSD: not present
  APM: not present
  GPT: not present

Creating new GPT entries.
Disk /dev/sdg: 3519069872 sectors, 1.6 TiB
Logical sector size: 512 bytes
Disk identifier (GUID): B19A7DC5-52A5-44AD-B295-51C8853A9EBB
Partition table holds up to 128 entries
First usable sector is 34, last usable sector is 3519069838
Partitions will be aligned on 2048-sector boundaries
Total free space is 3519069805 sectors (1.6 TiB)

And here's smartctl:

# smartctl -x /dev/sdg 
smartctl 6.6 2016-05-31 r4324 [x86_64-linux-4.8.0-49-generic] (local build)
Copyright (C) 2002-16, Bruce Allen, Christian Franke, www.smartmontools.org

Model Family:     Western Digital Purple
Device Model:     WDC WD40PURX-64GVNY0
Serial Number:    WD-WCC4E3YY1VKE
LU WWN Device Id: 5 0014ee 2b849189a
Firmware Version: 80.00A80
User Capacity:    4,000,787,030,016 bytes [4.00 TB]
Sector Sizes:     512 bytes logical, 4096 bytes physical
Rotation Rate:    5400 rpm
Device is:        In smartctl database [for details use: -P show]
ATA Version is:   ACS-2 (minor revision not indicated)
SATA Version is:  SATA 3.0, 6.0 Gb/s (current: 1.5 Gb/s)
Local Time is:    Wed Apr 26 11:23:10 2017 IDT
SMART support is: Available - device has SMART capability.
SMART support is: Enabled
AAM feature is:   Unavailable
APM feature is:   Unavailable
Rd look-ahead is: Enabled
Write cache is:   Enabled
ATA Security is:  Disabled, NOT FROZEN [SEC1]
Write SCT (Get) Feature Control Command failed: Read of ATA output registers not implemented [JMicron]
Wt Cache Reorder: Unknown (SCT Feature Control command failed)

Here's lsusb:

# lsusb | grep SATA
Bus 001 Device 002: ID 152d:2338 JMicron Technology Corp. / JMicron USA Technology Corp. 
  JM20337 Hi-Speed USB to SATA & PATA Combo Bridge

I've search around for something like a size limit for USB mass storage devices, but that doesn't seem to be the case.

[Update]: After looking at the discussions pointed to by @Mitch, I've tried setting the drive to "Advanced Format" using a jumper, without success - after setting the jumper, the drive still identifies as "Sector size: 512 bytes logical, 4096 bytes physical".

I'd appreciate any thoughts on the subject.

  • Have you tried a different adapter? See Here. – Mitch Apr 26 '17 at 8:55
  • Unfortunately, I don't have one available. Also, the problem described in your link is somewhat different than mine - as I understand it, gdisk reported 4TB available on the OPs system, which is not the case on my system. – Guss Apr 26 '17 at 9:16
  • Why not reverse the operation? Install the new 4TB in the computer and stick the 1TB on the USB adapter? Most linuxes will still boot and work in that fashion (albeit a bit slowly), as long as the BIOS is forced to boot from the USB. – sergtech Apr 27 '17 at 8:23
  • @sergtech-S.Dragomir - its not the main drive. The drive to be replaced is part of a BTRFS array. But that sounds very doable - I'll try that. Mind writing it up as an answer? – Guss Apr 27 '17 at 8:25

A possible solution to the problem would be to directly attach the larger 4TB drive to the computer SATA port and the smaller drive on the usb adapter.

Most new Linux Systems could run directly off the USB, as long as the BIOS would be forced to boot off USB (although a bit slowly).

An indirect solution could follow from here or here. It seems other people are having similar problems due to this specific JMicron adapter, whose quirks were fixed but then re-appeared. Maybe try running a different kernel where the bug hadn't re-occurred.

  • I didn't try the quirks mode, but I got a new adapter and that works fine. I'll try to mess with it when I finish migrating and have a spare 2TB drive to play with :-) – Guss Apr 27 '17 at 21:09

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