# [solved] Using the full space of a 3TB hard disk

## majoron

Hello,

I've just bought a new 3TB hard disk (Verbatim Store 'n' Save), and I sadly find out that my system only sees 2.2 TB (2199 GB).

Of course I made a GPT and I have GPT support in the kernel.

The way I have always done >2TB partitions is (but never used in the system I'm refering to here):

```
# parted /dev/sdc

(parted) mklabel gpt

(parted) unit %

(parted) mkpart primary ext4 0 100

(parted) quit

# mkfs.ext4 /dev/sdc1
```

But this time, as I said, it fails (only 2.2TB detected).

Now, I'm asking myself if it is a problem with BIOS. Actually I was looking at the BIOS (with hard disk plugged in and on), but couldn't find any relevant option to enable. Perhaps I need a BIOS update, but as I don't have experience with this stuff I'm a bit reluctant.

Could you please help me to determine what is the source of the problem?

As I said, if I can avoid it, I would prefer to not update the BIOS. Unless it is stricly necessary.

Any insight on this is appreciated.

TIA.

Regards

----------

## Maitreya

Some cheaper/older usb<->sata link have this too. Including older RAID cards. I'm sorry but I'm afraid it's the board and not the os or disk.

----------

## toralf

Hhm, but TB != TiBi, meaning

```
$ expr 3000000000000 / 1024 / 1024 / 1024

2793
```

Furthermore ext3 and above reserves 5% for root, so I'd expect not more than 2.65 TB (with 1 TB = 1024^4 Bytes)

----------

## majoron

 *toralf wrote:*   

> Hhm, but TB != TiBi, meaning
> 
> ```
> $ expr 3000000000000 / 1024 / 1024 / 1024
> 
> ...

 

Ok. I know. Still I would like to enjoy the extra space.

----------

## majoron

 *Maitreya wrote:*   

> Some cheaper/older usb<->sata link have this too. Including older RAID cards. I'm sorry but I'm afraid it's the board and not the os or disk.

 Thanks for your comment.

If you are right, I'm a bit worried. The BIOS update offered by Asus (the manufacturer of my motherboard) doesn't seem to include any change relevant for my problem, unless "Improve memory compatibility" implies some sort of solution.

----------

## fturco

I calculated that the available space for a 3 TB disk should be 2.59 TiB (if you exclude reserved blocks). Anyway you can check the total (unformatted) disk size with parted. Assuming /dev/sda is your disk:

```
parted /dev/sda unit TiB print
```

It should return a value of around 2.73 TiB.

----------

## majoron

 *fturco wrote:*   

> I calculated that the available space for a 3 TB disk should be 2.59 TiB (if you exclude reserved blocks). Anyway you can check the total (unformatted) disk size with parted. Assuming /dev/sda is your disk:
> 
> ```
> parted /dev/sda unit TiB print
> ```
> ...

 I agree.

I expect a raw size of 2794 GiB. And I've been reported by parted that the disk is 2199 GiB large (if I remember correctly).

Now, I'm sorry if the words in my original post are misleading (or if my usage of the units was sloppy), but what I'm talking about in this thread is getting the extra 595 GiB (2794-2199) that are physically in my device.

Or are you suggesting to forget about those 595 GiB and, for the sake of safety, do not update the BIOS?

Regards

----------

## srs5694

Please post the output of the following commands (run as root):

```
parted /dev/sdc print

gdisk -l /dev/sdc

hdparm -N /dev/sdc
```

You may need to install the "gptfdisk" package to run the second command. Change "/dev/sdc" to whatever the disk's device filename is. Also, please specify whether this is an internal or an external disk, and what type of interface it uses (PATA, SATA, eSATA, USB, etc.).

The motherboard's firmware (BIOS or EFI) should not be limiting how the disk is "perceived" by Linux, because Linux accesses the disk directly, without involving the firmware. This could be a parted bug, a limitation in an interface (USB interfaces are particularly prone to this sort of thing), or incorrect setting of the Host Protected Area (HPA) feature on the disk.

----------

## majoron

 *srs5694 wrote:*   

> Please post the output of the following commands (run as root):
> 
> ```
> parted /dev/sdc print
> 
> ...

 

Thank you for the interesting answer.

It is an external hard disk. The interface is USB. In principle it should be compatible with USB 1.1, 2.0 and 3.0 (or that is said in the docs).

Here it goes:

```
# parted /dev/sdc print

Model: TOSHIBA DT01ACA300 (scsi)

Disk /dev/sdc: 2199GB

Sector size (logical/physical): 512B/512B

Partition Table: gpt

Disk Flags: 

Numero  Inicio  Fin     Tamaño  Sistema de ficheros  Nombre   Banderas

 1      1049kB  2199GB  2199GB  ext4                 primary

# gdisk -l /dev/sdc

GPT fdisk (gdisk) version 0.8.6

Partition table scan:

  MBR: protective

  BSD: not present

  APM: not present

  GPT: present

Found valid GPT with protective MBR; using GPT.

Disk /dev/sdc: 4294965248 sectors, 2.0 TiB

Logical sector size: 512 bytes

Disk identifier (GUID): 02E748A3-BA1A-4A06-81E4-AB46BF5A6542

Partition table holds up to 128 entries

First usable sector is 34, last usable sector is 4294965214

Partitions will be aligned on 2048-sector boundaries

Total free space is 4029 sectors (2.0 MiB)

Number  Start (sector)    End (sector)  Size       Code  Name

   1            2048      4294963199   2.0 TiB     0700  primary

# hdparm -N /dev/sdc

/dev/sdc:

SG_IO: bad/missing sense data, sb[]:  f0 00 01 00 50 4d 00 0a a0 50 a3 af 00 1d 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

 max sectors   = 5860533168/1(5860533168?), HPA setting seems invalid (buggy kernel device driver?)
```

This last info is odd. buggy kernel driver?. Am I missing some kernel option? Defective disk?

BTW, the disk comes with a warning. It is said that the unit is splitted into two pieces because some OSs do not support >2TB partitions. However I didn't see a second partition never.

Best regards

----------

## fturco

 *majoron wrote:*   

> BTW, the disk comes with a warning. It is said that the unit is splitted into two pieces because some OSs do not support >2TB partitions. However I didn't see a second partition never.

 

I don't have experience with multi-terabyte hard disks, but maybe you should check for a second device (such as /dev/sdd) instead of a second partition. It may be helpful to use the following command after inserting the hard disk:

```
watch -n 1 "dmesg | tail"
```

EDIT: Also it seems you have an HPA which is not visible to the operating system. This howto could be useful for disabling it. I would back up any data before trying that.

----------

## Jaglover

Out of curiosity ... I normally do not use any partition tables for a single-filesystem drive (unless it is bootable). Have you tried creating a filesystem on sdc?

mkfs.xfs -f /dev/sdc for instance.

----------

## majoron

 *Jaglover wrote:*   

> Out of curiosity ... I normally do not use any partition tables for a single-filesystem drive (unless it is bootable). Have you tried creating a filesystem on sdc?
> 
> mkfs.xfs -f /dev/sdc for instance.

 I have done it. Again 2TB:

```
# parted /dev/sdc print

Model: TOSHIBA DT01ACA300 (scsi)

Disk /dev/sdc: 2199GB

Sector size (logical/physical): 512B/512B

Partition Table: loop

Disk Flags: 

Numero  Inicio  Fin     Tamaño  Sistema de ficheros  Banderas

 1      0.00B   2199GB  2199GB  xfs

```

Thanks anyway.

----------

## srs5694

 *majoron wrote:*   

> 
> 
> ```
> # parted /dev/sdc print
> 
> ...

 

Both parted and gdisk see the disk as being 2TiB in size. (parted isn't reporting a precise number of sectors, but it's probably the same as what gdisk is seeing.)

 *majoron wrote:*   

> 
> 
> ```
> # hdparm -N /dev/sdc
> 
> ...

 

This has my alarm bells ringing. My suspicion is that the manufacturer has done something weird with the USB interface in order to work around the 2TiB limit of MBR.

 *fturco wrote:*   

>  *majoron wrote:*   BTW, the disk comes with a warning. It is said that the unit is splitted into two pieces because some OSs do not support >2TB partitions. However I didn't see a second partition never. 
> 
> I don't have experience with multi-terabyte hard disks, but maybe you should check for a second device (such as /dev/sdd) instead of a second partition. It may be helpful to use the following command after inserting the hard disk:

 

This is worth trying -- just doing "ls /dev/sd?" will show you all your disk devices. You can try unplugging the disk, issuing that command, plugging it back in again, waiting a few seconds, and then issuing the command again to see if more than one device shows up.

If that doesn't help, or if it does and you want to use the disk as a single unit, I recommend returning it to the store and buying another one. If I'm right and the manufacturer is doing weird things in its firmware, then the odds are that it will continue to cause problems in the future. Historically, products that try to be "clever" in this sort of way end up being more trouble than they're worth. It's better to use something that just presents itself as a full-sized drive, which Linux can handle just fine, even if, say, Windows XP couldn't use it.

----------

## majoron

Thank you again for the interest.

 *fturco wrote:*   

>  *majoron wrote:*   BTW, the disk comes with a warning. It is said that the unit is splitted into two pieces because some OSs do not support >2TB partitions. However I didn't see a second partition never. 
> 
> I don't have experience with multi-terabyte hard disks, but maybe you should check for a second device (such as /dev/sdd) instead of a second partition. It may be helpful to use the following command after inserting the hard disk:
> 
> ```
> ...

 

Nope. Only /dev/sdc and /dev/sdc1 appear (of course, sdc1 is the partition I made).

However, another devide shows up: /dev/sg3, which I doubt is another hard disk (I tried to open it with parted and fdisk, and failed).

 *Quote:*   

> EDIT: Also it seems you have an HPA which is not visible to the operating system. This howto could be useful for disabling it. I would back up any data before trying that.

 

I'm still investigating this. I'm inclined to think that this is what is going on, or some sort of variation, as srs5694 said.

However, I read in the man page of hdparm the following (when talking about the -N option):

 *Quote:*   

> Host Protected Area (HPA).  This area is often used by computer makers to hold diagnostic software,
> 
>               and/or a copy of the originally provided operating system for recovery purposes.  Another possible use is to hide the true capacity of a
> 
>               very  large  disk  from a BIOS/system that cannot normally cope with drives of that size (eg. most current {2010} BIOSs cannot deal with
> ...

 

So I'm afraid that

1) I need to remove the HPA (which I still couldn't do, or that is what I think), and

2) most likely update the BIOS anyway because my motherboard was bought in 2010 and actually I think it is older than that.

At least this is what I understood. Other insights?

----------

## majoron

 *srs5694 wrote:*   

>  *majoron wrote:*   
> 
> ```
> # parted /dev/sdc print
> 
> ...

 

Thank's for the reply. I'm afraid that the option of returning the disk is becoming more solid. In that case the questions would be, what else to buy? and, will my motherboard support it?

----------

## NeddySeagoon

majoron,

```
hdparm -N /dev/sdc

/dev/sdc:

SG_IO: bad/missing sense data, sb[]:  f0 00 01 00 50 4d 00 0a a0 50 a3 af 00 1d 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

 max sectors   = 5860533168/1(5860533168?), HPA setting seems invalid (buggy kernel device driver?)
```

and your comment about the disk being split into two gives me a pointer.

Your drive my be programmed to lie about it real size by having the missing space allocated to a Host Protected Area, which is what the HPA reference in your message above is.  This is, or was, a small area at the end of a drive, hidden from the operating system, often used for a system restore area.  Special software is needed to access it, as the Host cannot see the space - hence Host Protected Area.

It should be listed in dmesg if its there.  If you do have a HPA, you may use Linux to remove it to get all of your space back.

Put your dmesg onto a pastebin site and post a link if you want us to review it.

-- Edit --

Max Sectors=5860533168 is 3000592982016 B or three salesmans Tb.

----------

## s4e8

you must enable kernel config

CONFIG_SCSI_MULTI_LUN=y

----------

## srs5694

 *majoron wrote:*   

> Nope. Only /dev/sdc and /dev/sdc1 appear (of course, sdc1 is the partition I made).
> 
> However, another devide shows up: /dev/sg3, which I doubt is another hard disk (I tried to open it with parted and fdisk, and failed).

 

If there's a /dev/sg3, there should also be a /dev/sg, which would be the part of the "disk" that holds the partition table. Ordinarily, /dev/s? devices (/dev/sda, /dev/sdb, and so on) point to a whole disk, whereas /dev/s?# devices (/dev/sda7, /dev/sdb2, etc.) point to partitions.

 *Quote:*   

> 1) I need to remove the HPA (which I still couldn't do, or that is what I think), and

 

Adjusting the HPA might work, and it might be worth trying this; however, HPA is a feature that's built into the hard disk itself. In order to manipulate the HPA, you've got to be able to send the appropriate commands to the disk, via hdparm. The problem is that USB disk interfaces add a layer to the interactions between the OS and the disk, and I don't know offhand what is typically done with the HPA data, much less what your specific enclosure does. Adjusting the HPA values might work; or it might do nothing; or it might do something weird, up to the point of rendering the disk unusable. If you plan to return the disk to the store if nothing else works, taking the risk might be worthwhile, and is even ethically justified IMHO. (The manufacturer has provided something non-standard and non-functional, and they'll need to deal with the return at the factory anyhow. They almost certainly know how to correct any issues that an adjustment of the HPA might cause.)

 *Quote:*   

> 2) most likely update the BIOS anyway because my motherboard was bought in 2010 and actually I think it is older than that.

 

The BIOS is a red herring. BIOS limitations are important only in the early stages of booting from a hard disk; once Linux takes control, the kernel communicates directly with the disk, bypassing the BIOS and any limitations it might have. Even if you're booting from the disk (which I'm guessing you're not, since it's an external disk), Linux can cope fine by putting a small /boot partition near the start of the disk, which won't be affected by the BIOS limitations.

To be clear: Your problem is not a motherboard BIOS issue, and upgrading your motherboard's BIOS will not fix the problem.

----------

## Jaglover

Actually, I was reading up on HPA and found some forum thread where people blamed motherboard BIOS for creating HPA on hard drive. If I recall correctly they were talking about 2010 motherboards ...

Edit: http://lime-technology.com/forum/index.php?topic=10866.0

----------

## srs5694

I've never before heard of a motherboard's BIOS setting the HPA on a hard disk unbidden. Of course, that's no guarantee that it never happens; my knowledge is necessarily limited. My hunch is that if it does happen this way, the BIOS would be setting the HPA on RAIDed disks as a way to store RAID metadata. (In this sense, the setting of HPA data wouldn't really be "unbidden;" it would be implicit in the request to set up the disk for use in a RAID array.) If I'm right, it's unlikely that your single external USB disk would have an HPA set for such a purpose; it's more likely that the external enclosure's firmware would be setting the HPA as a way of splitting a single over-2TiB disk into two virtual disks to help OSes that can't handle over-2TiB disks. This is particularly true because you paraphrased a notice from the disk's manufacturer to the effect that it's split into two parts. Overall, the evidence points strongly toward the enclosure's USB interface firmware being the culprit, not your motherboard's BIOS.

----------

## NeddySeagoon

majoron, 

It can also be that the SATA/USB interface in the enclosure is brain dead and is only sending the 32bit LBA data to the PC.

Thats game over, the most that can hold is 4G sectors, or your 2.2Tb.

The 48bit LBA data is sent in a different location in the response to the identify command.

What does lsusb say about your drive/enclosure?

In particular, the vendor and device ID.

----------

## s4e8

This is a USB3 enclosure, there's no HPA. According the review:

 *Quote:*   

> What’s more, the 3TB model appears to Windows as two physical disks (to ensure compatibility with older operating systems) and, frustratingly, there’s no way to recombine them into a single volume.
> 
> 

 

It just a 2 LUN USB storage device.

----------

## NeddySeagoon

s4e8

Thats just silly - even WinXP has an update to deal with HDD bigger than the MSDOS Partition Table Limit.

Its called NTFS.

It would be good to know the vendor and device IDs, so we know exactly whats in the USB enclosure.

----------

## Maitreya

 *NeddySeagoon wrote:*   

> majoron, 
> 
> It can also be that the SATA/USB interface in the enclosure is brain dead and is only sending the 32bit LBA data to the PC.
> 
> Thats game over, the most that can hold is 4G sectors, or your 2.2Tb.
> ...

 

Like I posted earlier, I've seen this several times.

----------

## srs5694

 *NeddySeagoon wrote:*   

> Thats just silly - even WinXP has an update to deal with HDD bigger than the MSDOS Partition Table Limit.
> 
> Its called NTFS.

 

NTFS is normally used on partitioned devices, and if the partitioning system in question is MBR, NTFS will be limited to 2TiB partitions. That said, it is possible to use NTFS on an unpartitioned disk, which would enable it to be used on larger disks. I don't know offhand how Windows XP would cope with this, though. NTFS can also, of course, be used on GPT-partitioned disks, but most versions of Windows XP can't handle GPT.

As a practical matter, some USB drive enclosures convert 512-byte sectors to 4096-byte sectors. This raises the MBR limit from 2TiB to 16TiB. Some BIOSes can't boot from such disks, though, and the disk will become unreadable if it's removed from the enclosure and connected directly to a disk. (I've even heard of enclosures with both USB and eSATA interfaces, which present the disk differently depending on which interface is used. That's a serious problem, of course.)

 *Quote:*   

> It would be good to know the vendor and device IDs, so we know exactly whats in the USB enclosure.

 

I agree this might be helpful, since it would enable doing some Internet searches, or checking vendor technical documents, to discover what's actually going on with the specific disk in question.

----------

## NeddySeagoon

srs5694,

Well said, thank you.   I mixed up the two issues.

----------

## majoron

Hello,

Thank you very much for the interest and the good comments here.

I had some problems due to a series of unfortunate coincidences starting with a wrong "grub-install" aimed at doing what s4e8 suggested

 *s4e8 wrote:*   

> you must enable kernel config
> 
> CONFIG_SCSI_MULTI_LUN=y

 

BTW, thank you very much, s4e8, for the detail. I was missing this option.

Now, after being able to boot again, I can see that the disk is seen indeed as two devices: I have now sdc and sdd (of course sdc1 and sdd1 are the partitions). Somehow the effect of the HPA is to artificially split the disk.

In this situation my preferred strategy would be to proceed safely, avoiding any risky step. After all I have access to all the space I bought...

I'll comment below on other comments.

----------

## majoron

 *NeddySeagoon wrote:*   

> majoron,
> 
> ```
> hdparm -N /dev/sdc
> 
> ...

 

I posted on pastebin the part that shows up when the disk is switched on.

Do you need the full dmesg?

Again, thank you.

----------

## NeddySeagoon

majoron,

All is well - you need to read Using the Verbatim Mode Change Tool

Unfortunately, it needs Windows.

This tool lets you switch between normal mode, where you see all of your drive in one piece and the two pieces you have now, which makes for easy living with MSDOS Partitions.

This switch destroys your data.

----------

## majoron

Thank you NeddySaegoon for your help.

The hard disk, as I wrote above, is a Verbatim Store 'N' Save 3TB usb3.0 external hard disk. I have other verbatim products and no particular complain about them, and this one had a special price. Now I know why   :Evil or Very Mad: 

Just for completeness; I add the lsusb info:

```
Bus 001 Device 004: ID 18a5:022a Verbatim, Ltd 

Device Descriptor:

  bLength                18

  bDescriptorType         1

  bcdUSB               2.10

  bDeviceClass            0 (Defined at Interface level)

  bDeviceSubClass         0 

  bDeviceProtocol         0 

  bMaxPacketSize0        64

  idVendor           0x18a5 Verbatim, Ltd

  idProduct          0x022a 

  bcdDevice            1.00

  iManufacturer          10 Verbatim

  iProduct               11 Desktop USB3.0 Drive

  iSerial                 3 18A5022A0000E189

  bNumConfigurations      1

  Configuration Descriptor:

    bLength                 9

    bDescriptorType         2

    wTotalLength           32

    bNumInterfaces          1

    bConfigurationValue     1

    iConfiguration          4 USB Mass Storage

    bmAttributes         0xc0

      Self Powered

    MaxPower                2mA

    Interface Descriptor:

      bLength                 9

      bDescriptorType         4

      bInterfaceNumber        0

      bAlternateSetting       0

      bNumEndpoints           2

      bInterfaceClass         8 Mass Storage

      bInterfaceSubClass      6 SCSI

      bInterfaceProtocol     80 Bulk-Only

      iInterface              6 MSC Bulk-Only Transfer

      Endpoint Descriptor:

        bLength                 7

        bDescriptorType         5

        bEndpointAddress     0x81  EP 1 IN

        bmAttributes            2

          Transfer Type            Bulk

          Synch Type               None

          Usage Type               Data

        wMaxPacketSize     0x0200  1x 512 bytes

        bInterval               0

      Endpoint Descriptor:

        bLength                 7

        bDescriptorType         5

        bEndpointAddress     0x02  EP 2 OUT

        bmAttributes            2

          Transfer Type            Bulk

          Synch Type               None

          Usage Type               Data

        wMaxPacketSize     0x0200  1x 512 bytes

        bInterval               0

Binary Object Store Descriptor:

  bLength                 5

  bDescriptorType        15

  wTotalLength           42

  bNumDeviceCaps          3

  USB 2.0 Extension Device Capability:

    bLength                 7

    bDescriptorType        16

    bDevCapabilityType      2

    bmAttributes   0x00000002

      Link Power Management (LPM) Supported

  SuperSpeed USB Device Capability:

    bLength                10

    bDescriptorType        16

    bDevCapabilityType      3

    bmAttributes         0x00

    wSpeedsSupported   0x000e

      Device can operate at Full Speed (12Mbps)

      Device can operate at High Speed (480Mbps)

      Device can operate at SuperSpeed (5Gbps)

    bFunctionalitySupport   1

      Lowest fully-functional device speed is Full Speed (12Mbps)

    bU1DevExitLat          10 micro seconds

    bU2DevExitLat          32 micro seconds

  Container ID Device Capability:

    bLength                20

    bDescriptorType        16

    bDevCapabilityType      4

    bReserved               0

    ContainerID             {00010203-0405-0607-0800-000000000000}

Device Status:     0x0001

  Self Powered

Bus 001 Device 008: ID 18a5:0400 Verbatim, Ltd 

Device Descriptor:

  bLength                18

  bDescriptorType         1

  bcdUSB               2.10

  bDeviceClass            0 (Defined at Interface level)

  bDeviceSubClass         0 

  bDeviceProtocol         0 

  bMaxPacketSize0        64

  idVendor           0x18a5 Verbatim, Ltd

  idProduct          0x0400 

  bcdDevice            0.01

  iManufacturer           1 Verbatim

  iProduct                2 USB 3.0 Desktop HD

  iSerial                 3 306219105620

  bNumConfigurations      1

  Configuration Descriptor:

    bLength                 9

    bDescriptorType         2

    wTotalLength           32

    bNumInterfaces          1

    bConfigurationValue     1

    iConfiguration          0 

    bmAttributes         0xc0

      Self Powered

    MaxPower                8mA

    Interface Descriptor:

      bLength                 9

      bDescriptorType         4

      bInterfaceNumber        0

      bAlternateSetting       0

      bNumEndpoints           2

      bInterfaceClass         8 Mass Storage

      bInterfaceSubClass      6 SCSI

      bInterfaceProtocol     80 Bulk-Only

      iInterface              0 

      Endpoint Descriptor:

        bLength                 7

        bDescriptorType         5

        bEndpointAddress     0x81  EP 1 IN

        bmAttributes            2

          Transfer Type            Bulk

          Synch Type               None

          Usage Type               Data

        wMaxPacketSize     0x0200  1x 512 bytes

        bInterval              20

      Endpoint Descriptor:

        bLength                 7

        bDescriptorType         5

        bEndpointAddress     0x02  EP 2 OUT

        bmAttributes            2

          Transfer Type            Bulk

          Synch Type               None

          Usage Type               Data

        wMaxPacketSize     0x0200  1x 512 bytes

        bInterval              20

Binary Object Store Descriptor:

  bLength                 5

  bDescriptorType        15

  wTotalLength           22

  bNumDeviceCaps          2

  USB 2.0 Extension Device Capability:

    bLength                 7

    bDescriptorType        16

    bDevCapabilityType      2

    bmAttributes   0x00000002

      Link Power Management (LPM) Supported

  SuperSpeed USB Device Capability:

    bLength                10

    bDescriptorType        16

    bDevCapabilityType      3

    bmAttributes         0x00

    wSpeedsSupported   0x000e

      Device can operate at Full Speed (12Mbps)

      Device can operate at High Speed (480Mbps)

      Device can operate at SuperSpeed (5Gbps)

    bFunctionalitySupport   1

      Lowest fully-functional device speed is Full Speed (12Mbps)

    bU1DevExitLat           0 micro seconds

    bU2DevExitLat           0 micro seconds

Device Status:     0x0001

  Self Powered

```

For the moment, I think I will use as it is: from your comments I think it's wise to not to try fancy things with the HPA and just use it as two disks, although a bit uncomfortable.

Next time I'll try to be more careful when choosing hardware.

Anyway, thank you, also srs5694 and Jaglover for the other interesting comments about this issue.

Strictly speaking the thread title's question has been already answered, so I'll mark it as solved.

Thanks to all.

----------

## Jaglover

You are welcome. Although I do not think this has anything to do with HPA. I'd contact the customer support and let them know splitting the drive 'just in case the customer is using a crappy OS' is not the solution, also I'd ask how to overcome this in POSIX environment.

----------

## NeddySeagoon

majoron,

It doesn't have a HPA. Its a standard HDD inside the enclosure.

However the enclosure USB/SATA controller can play tricks to make the one drive appear as two smaller drives, its supplied with this enabled.

You can turn this off if you want to - there is/was a Windows program on the disk to do that.

----------

## majoron

 *NeddySeagoon wrote:*   

> majoron,
> 
> All is well - you need to read Using the Verbatim Mode Change Tool
> 
> Unfortunately, it needs Windows.
> ...

 

Ah! Thank you!

I Don't have Windows. And unfortunately I don't manage to get it working under wine (it does not find the disk).

Anyway, thank you, really.

Best regards.

----------

## majoron

 *Jaglover wrote:*   

> You are welcome. Although I do not think this has anything to do with HPA. I'd contact the customer support and let them know splitting the drive 'just in case the customer is using a crappy OS' is not the solution, also I'd ask how to overcome this in POSIX environment.

 

This could be a good thing to try...

Thanks again.

----------

## majoron

 *NeddySeagoon wrote:*   

> majoron,
> 
> It doesn't have a HPA. Its a standard HDD inside the enclosure.
> 
> However the enclosure USB/SATA controller can play tricks to make the one drive appear as two smaller drives, its supplied with this enabled.
> ...

 

I'm a bit slow in answering   :Embarassed: 

In any case, I understand that behind that problem there are good (monetary) reasons (they avoid many refunds). But it's so... arghh!

----------

## srs5694

 *majoron wrote:*   

> Now, after being able to boot again, I can see that the disk is seen indeed as two devices: I have now sdc and sdd (of course sdc1 and sdd1 are the partitions). Somehow the effect of the HPA is to artificially split the disk.
> 
> In this situation my preferred strategy would be to proceed safely, avoiding any risky step. After all I have access to all the space I bought...

 

If you're using the disk exclusively from Linux, you could use LVM or RAID features to re-connect both "drives" into one unit, if that would be more convenient than using it as two "drives." That's adding complexity when simplifying the matter would be a better choice, though. IMHO, it's probably better to look into that program that NeddySeagoon has located. Even if you don't normally run Windows, plugging the disk into a Windows computer just to run that one program is probably worth doing.

----------

## majoron

 *srs5694 wrote:*   

>  *majoron wrote:*   Now, after being able to boot again, I can see that the disk is seen indeed as two devices: I have now sdc and sdd (of course sdc1 and sdd1 are the partitions). Somehow the effect of the HPA is to artificially split the disk.
> 
> In this situation my preferred strategy would be to proceed safely, avoiding any risky step. After all I have access to all the space I bought... 
> 
> If you're using the disk exclusively from Linux, you could use LVM or RAID features to re-connect both "drives" into one unit, if that would be more convenient than using it as two "drives." That's adding complexity when simplifying the matter would be a better choice, though. IMHO, it's probably better to look into that program that NeddySeagoon has located. Even if you don't normally run Windows, plugging the disk into a Windows computer just to run that one program is probably worth doing.

 

I also thought about somehow combining the disks doing a RAID or something, but as you mention, that's not ideal and I would prefer to stay on the safe side for the moment.

On the other hand, I really don't have access to windoze, nor I'll have it in the short time (after all I bought the disk because I need it with some urgency): all the people I interact usually with, as far as I remember, use either Linux or Mac...

----------

## srs5694

 *majoron wrote:*   

> On the other hand, I really don't have access to windoze, nor I'll have it in the short time (after all I bought the disk because I need it with some urgency): all the people I interact usually with, as far as I remember, use either Linux or Mac...

 

If you bought it locally, take it to the store and ask to run the software on one of their computers. If they refuse (as they might), return the drive. It's not worth the hassle of dealing with half-baked workarounds, IMO.

----------

