[SOLVED] Two physical devices on one HDD.

MacDaddy1660B · 04-03-2019, 12:57 PM

Hi everyone,

I have a hard drive that used to be part of a ZFS pool, but has since been removed. I want to use it as a backup drive. When I plug the drive in, it shows up as two physical devices:

Code:

/dev/sdb
/dev/sdc

I can verify these two physical devices are on the same drive by looking at the serial number associated with each after doing

Code:

hdparm -I /dev/sd[bc]

.

I'd like to merge these two devices into one so that I can use the drive as a single backup drive. Could anybody help me with this, or point me in a direction where I can find this information? Google is no help, I'm afraid. Thanks!

pan64 · 04-03-2019, 01:53 PM

I have never heard about that. What kind of hdd is it? How is it plugged in?

sevendogsbsd · 04-03-2019, 02:01 PM

Is it simply partitioned or is it a hybrid device, which has an SSD and a spinning drive internally.

MacDaddy1660B · 04-03-2019, 02:13 PM

Thanks for the replies.

This is a regular spinning desktop HDD. I have it plugged in via a USB enclosure.

From lsblk:

Code:

$ lsblk
NAME   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda      8:0    0 119.2G  0 disk 
├─sda1   8:1    0    64M  0 part /boot/efi
└─sda2   8:2    0 119.1G  0 part /
sdb      8:16   0     2T  0 disk 
sdc      8:32   0 746.5G  0 disk

Here's the output from hdparm.

Code:

$ sudo hdparm -I /dev/sd[bc]

/dev/sdb:

ATA device, with non-removable media
	Model Number:       Hitachi HDS5C3030ALA630                 
	Serial Number:      MJ1311YNG5XXGA
	Firmware Revision:  MEAOAA10
	Transport:          Serial, ATA8-AST, SATA 1.0a, SATA II Extensions, SATA Rev 2.5, SATA Rev 2.6; Revision: ATA8-AST T13 Project D1697 Revision 0b
Standards:
	Used: unknown (minor revision code 0x0029) 
	Supported: 8 7 6 5 
	Likely used: 8
Configuration:
	Logical		max	current
	cylinders	16383	16383
	heads		16	16
	sectors/track	63	63
	--
	CHS current addressable sectors:    16514064
	LBA    user addressable sectors:   268435455
	LBA48  user addressable sectors:  5860533168
	Logical  Sector size:                   512 bytes
	Physical Sector size:                   512 bytes
	device size with M = 1024*1024:     2861588 MBytes
	device size with M = 1000*1000:     3000592 MBytes (3000 GB)
	cache/buffer size  = 26129 KBytes (type=DualPortCache)
	Form Factor: 3.5 inch
	Nominal Media Rotation Rate: 5700
Capabilities:
	LBA, IORDY(can be disabled)
	Queue depth: 32
	Standby timer values: spec'd by Standard, no device specific minimum
	R/W multiple sector transfer: Max = 16	Current = 0
	Advanced power management level: disabled
	DMA: mdma0 mdma1 mdma2 udma0 udma1 udma2 udma3 udma4 udma5 *udma6 
	     Cycle time: min=120ns recommended=120ns
	PIO: pio0 pio1 pio2 pio3 pio4 
	     Cycle time: no flow control=120ns  IORDY flow control=120ns
Commands/features:
	Enabled	Supported:
	   *	SMART feature set
	    	Security Mode feature set
	   *	Power Management feature set
	    	Write cache
	   *	Look-ahead
	   *	Host Protected Area feature set
	   *	WRITE_BUFFER command
	   *	READ_BUFFER command
	   *	NOP cmd
	   *	DOWNLOAD_MICROCODE
	    	Advanced Power Management feature set
	    	Power-Up In Standby feature set
	   *	SET_FEATURES required to spinup after power up
	    	SET_MAX security extension
	   *	48-bit Address feature set
	   *	Device Configuration Overlay feature set
	   *	Mandatory FLUSH_CACHE
	   *	FLUSH_CACHE_EXT
	   *	SMART error logging
	   *	SMART self-test
	    	Media Card Pass-Through
	   *	General Purpose Logging feature set
	   *	WRITE_{DMA|MULTIPLE}_FUA_EXT
	   *	64-bit World wide name
	   *	URG for READ_STREAM[_DMA]_EXT
	   *	URG for WRITE_STREAM[_DMA]_EXT
	   *	WRITE_UNCORRECTABLE_EXT command
	   *	{READ,WRITE}_DMA_EXT_GPL commands
	   *	Segmented DOWNLOAD_MICROCODE
	   *	unknown 119[7]
	   *	Gen1 signaling speed (1.5Gb/s)
	   *	Gen2 signaling speed (3.0Gb/s)
	   *	Gen3 signaling speed (6.0Gb/s)
	   *	Native Command Queueing (NCQ)
	   *	Host-initiated interface power management
	   *	Phy event counters
	   *	NCQ priority information
	    	Non-Zero buffer offsets in DMA Setup FIS
	    	DMA Setup Auto-Activate optimization
	    	Device-initiated interface power management
	    	In-order data delivery
	   *	Software settings preservation
	   *	SMART Command Transport (SCT) feature set
	   *	SCT Write Same (AC2)
	   *	SCT Error Recovery Control (AC3)
	   *	SCT Features Control (AC4)
	   *	SCT Data Tables (AC5)
Security: 
	Master password revision code = 65534
		supported
	not	enabled
	not	locked
	not	frozen
	not	expired: security count
	not	supported: enhanced erase
	more than 508min for SECURITY ERASE UNIT.
Logical Unit WWN Device Identifier: 5000cca228c2b269
	NAA		: 5
	IEEE OUI	: 000cca
	Unique ID	: 228c2b269
Checksum: correct

/dev/sdc:

ATA device, with non-removable media
	Model Number:       Hitachi HDS5C3030ALA630                 
	Serial Number:      MJ1311YNG5XXGA
	Firmware Revision:  MEAOAA10
	Transport:          Serial, ATA8-AST, SATA 1.0a, SATA II Extensions, SATA Rev 2.5, SATA Rev 2.6; Revision: ATA8-AST T13 Project D1697 Revision 0b
Standards:
	Used: unknown (minor revision code 0x0029) 
	Supported: 8 7 6 5 
	Likely used: 8
Configuration:
	Logical		max	current
	cylinders	16383	16383
	heads		16	16
	sectors/track	63	63
	--
	CHS current addressable sectors:    16514064
	LBA    user addressable sectors:   268435455
	LBA48  user addressable sectors:  5860533168
	Logical  Sector size:                   512 bytes
	Physical Sector size:                   512 bytes
	device size with M = 1024*1024:     2861588 MBytes
	device size with M = 1000*1000:     3000592 MBytes (3000 GB)
	cache/buffer size  = 26129 KBytes (type=DualPortCache)
	Form Factor: 3.5 inch
	Nominal Media Rotation Rate: 5700
Capabilities:
	LBA, IORDY(can be disabled)
	Queue depth: 32
	Standby timer values: spec'd by Standard, no device specific minimum
	R/W multiple sector transfer: Max = 16	Current = 0
	Advanced power management level: disabled
	DMA: mdma0 mdma1 mdma2 udma0 udma1 udma2 udma3 udma4 udma5 *udma6 
	     Cycle time: min=120ns recommended=120ns
	PIO: pio0 pio1 pio2 pio3 pio4 
	     Cycle time: no flow control=120ns  IORDY flow control=120ns
Commands/features:
	Enabled	Supported:
	   *	SMART feature set
	    	Security Mode feature set
	   *	Power Management feature set
	    	Write cache
	   *	Look-ahead
	   *	Host Protected Area feature set
	   *	WRITE_BUFFER command
	   *	READ_BUFFER command
	   *	NOP cmd
	   *	DOWNLOAD_MICROCODE
	    	Advanced Power Management feature set
	    	Power-Up In Standby feature set
	   *	SET_FEATURES required to spinup after power up
	    	SET_MAX security extension
	   *	48-bit Address feature set
	   *	Device Configuration Overlay feature set
	   *	Mandatory FLUSH_CACHE
	   *	FLUSH_CACHE_EXT
	   *	SMART error logging
	   *	SMART self-test
	    	Media Card Pass-Through
	   *	General Purpose Logging feature set
	   *	WRITE_{DMA|MULTIPLE}_FUA_EXT
	   *	64-bit World wide name
	   *	URG for READ_STREAM[_DMA]_EXT
	   *	URG for WRITE_STREAM[_DMA]_EXT
	   *	WRITE_UNCORRECTABLE_EXT command
	   *	{READ,WRITE}_DMA_EXT_GPL commands
	   *	Segmented DOWNLOAD_MICROCODE
	   *	unknown 119[7]
	   *	Gen1 signaling speed (1.5Gb/s)
	   *	Gen2 signaling speed (3.0Gb/s)
	   *	Gen3 signaling speed (6.0Gb/s)
	   *	Native Command Queueing (NCQ)
	   *	Host-initiated interface power management
	   *	Phy event counters
	   *	NCQ priority information
	    	Non-Zero buffer offsets in DMA Setup FIS
	    	DMA Setup Auto-Activate optimization
	    	Device-initiated interface power management
	    	In-order data delivery
	   *	Software settings preservation
	   *	SMART Command Transport (SCT) feature set
	   *	SCT Write Same (AC2)
	   *	SCT Error Recovery Control (AC3)
	   *	SCT Features Control (AC4)
	   *	SCT Data Tables (AC5)
Security: 
	Master password revision code = 65534
		supported
	not	enabled
	not	locked
	not	frozen
	not	expired: security count
	not	supported: enhanced erase
	more than 508min for SECURITY ERASE UNIT.
Logical Unit WWN Device Identifier: 5000cca228c2b269
	NAA		: 5
	IEEE OUI	: 000cca
	Unique ID	: 228c2b269
Checksum: correct

pan64 · 04-03-2019, 02:21 PM

this is exactly the same data, two times. This HDD has a sata interface, not usb. Probably it is your sata to usb adapter which doubles the device.

MacDaddy1660B · 04-03-2019, 02:30 PM

Quote:

Originally Posted by pan64

this is exactly the same data, two times. This HDD has a sata interface, not usb. Probably it is your sata to usb adapter which doubles the device.

Thank you, pan64. Yes, the HDD is a SATA drive in a USB enclosure. Agreed on the data from hdparm, but that does not explain the output from lsblk, which shows two different disks of two different sizes.

MensaWater · 04-03-2019, 02:45 PM

What does fdisk -l or parted tell you about them?

Install lsscsi and run that to see what it tells you about the disks. Maybe it has found something of which you're not aware?

MacDaddy1660B · 04-03-2019, 03:21 PM

One thing I notice that seems strange is the difference in model between the two i.e. HDS5C3030ALA630 vs. HDS5C3030ALALUN1

From fdisk -l:

Code:

$ sudo fdisk -l
[sudo] password for fatpie:                       
Disk /dev/sda: 119.2 GiB, 128035676160 bytes, 250069680 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: B55E3E01-A740-4F6B-B75A-54203EC3D775

Device      Start       End   Sectors   Size Type
/dev/sda1   65535    196604    131070    64M EFI System
/dev/sda2  196605 250000000 249803396 119.1G Linux filesystem


Disk /dev/sdb: 2 TiB, 2199023255040 bytes, 4294967295 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/sdc: 746.5 GiB, 801569726464 bytes, 1565565872 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes

parted:

Code:

$ sudo parted -l
Model: ATA Maximus-128GB (scsi)
Disk /dev/sda: 128GB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Disk Flags: 

Number  Start   End    Size    File system  Name  Flags
 1      33.6MB  101MB  67.1MB  fat32              boot, esp
 2      101MB   128GB  128GB   ext4


Error: /dev/sdb: unrecognised disk label
Model: Hitachi HDS5C3030ALA630 (scsi)                                     
Disk /dev/sdb: 2199GB
Sector size (logical/physical): 512B/512B
Partition Table: unknown
Disk Flags: 

Error: /dev/sdc: unrecognised disk label
Model: Hitachi HDS5C3030ALALUN1 (scsi)                                    
Disk /dev/sdc: 802GB
Sector size (logical/physical): 512B/512B
Partition Table: unknown
Disk Flags:

lsscsi:

Code:

$ lsscsi -L
[0:0:0:0]    disk    ATA      Maximus-128GB    7A    /dev/sda 
  device_blocked=0
  iocounterbits=32
  iodone_cnt=0xfc5f
  ioerr_cnt=0x101
  iorequest_cnt=0xff1c
  queue_depth=31
  queue_type=simple
  scsi_level=6
  state=running
  timeout=30
  type=0
[1:0:0:0]    disk    Hitachi  HDS5C3030ALA630  0200  /dev/sdb 
  device_blocked=0
  iocounterbits=32
  iodone_cnt=0xe9d0b
  ioerr_cnt=0x1
  iorequest_cnt=0xe9d0c
  queue_depth=1
  queue_type=none
  scsi_level=5
  state=running
  timeout=30
  type=0
[1:0:0:1]    disk    Hitachi  HDS5C3030ALALUN1 0200  /dev/sdc 
  device_blocked=0
  iocounterbits=32
  iodone_cnt=0x180
  ioerr_cnt=0x0
  iorequest_cnt=0x180
  queue_depth=1
  queue_type=none
  scsi_level=5
  state=running
  timeout=30
  type=0

pan64 · 04-04-2019, 03:39 AM

I would try another usb enclosure. probably.

MensaWater · 04-04-2019, 10:27 AM

In lsscsi you are showing:
[1:0:0:0] disk Hitachi HDS5C3030ALA630 0200 /dev/sdb
[1:0:0:1] disk Hitachi HDS5C3030ALALUN1 0200 /dev/sdc

In your earlier output you had the same model for sdb and sdc: HDS5C3030ALA630

The names seen in lsscsi appear to be extensions of that model. Both disks are devices on the same controller path, 1:0.0.

Online information only discusses the disk itself. What model of USB enclosure are you using? Does it have an interface that is traversible? You might want to research that to see if there is a guide for it.

Was this disk previously on the same system when it was ZFS? If may be the entries seen are recreations of what it saw when the USB enclosure with this disk was previously attached. If so removing the USB enclosure from the server, cleaning up old device entries, and re-attaching would help. I've had to do that when presenting LUNs from SAN that I've changed at SAN level.

Which Linux distro and version you're using?

Usually when you attach USB based drives it spits out a lot of information to the system log (/var/log/messages or journalctl if systemd). Examining those may give you information.

Also you might want to examine the USB enclosure itself to see if it has any physical options to reset the drive setup (while detached from any server).

Of course an easy way to get the space from both sdb and sdc together would be to pvcreate both then add both to a single volume group with vgcreate. You can then use lvcreate to create a logical volume using VG space. I highly recommend putting even single drives in LVM because changing its LVs later is much easier than resizing partitions. It also has the flexibility of letting you add and remove PVs (drives or partitions) to change the size of the VG.

Man LVM is a good place to start.

MacDaddy1660B · 04-04-2019, 01:30 PM

pan64 and MensaWater: thanks. I'm going to try swapping USB enclosures as soon as I can find someone with one they're willing to lend out. Seems I cannot find a model number on the enclosure, so who knows what it's doing.

The machine I have the drive connected to right now has never seen this device before, and is not the machine with the ZFS pool I speak of.

I'll report back whatever I can. Thanks again for the ideas.

MacDaddy1660B · 04-09-2019, 02:25 PM

After some looking, I have found that some older HDD enclosures (which this one is) have a limit of 2.0TB capacity. While I can't find a part or model number for this device and cannot confirm this, I suspect this is what is going on here. Thanks for the info, all!

pan64 · 04-10-2019, 02:39 AM

probably lsusb ?

MacDaddy1660B · 04-11-2019, 09:33 AM

Quote:

Originally Posted by pan64

probably lsusb ?

Good idea, but I can't find any information.

pan64 · 04-11-2019, 11:49 AM

you will find the usb device id and you may look for that id. (or just post it here?)