Usbhdd error 15

usbhdd error 15

forum.openmediavault.org › Dashboard › Forum › Storage › General. But those of us without the new iPad Pro or without USB-C hard drives This error message might also appear when your external drive is. Did a backup of a WD My Cloud EX4 as recommended by Corporate WD idiots. Now I can only access the dash for about 15-30 seconds. usbhdd error 15

Thematic video

Como Corrigir o Error Verification Failed 15 No Windows

Usbhdd error 15 - remarkable, the

External USB Hard Drive i/o error

I have an external USB hard drive that seems to have crashed. When I plug it into any of my computers it usually will not mount. Occasionally, it does mount, but then when I run an command for instance nothing ever comes back. The drive is split into four distinct partitions, the biggest one, and the one that I would like to recover is a data partition of about 953 GB.

When I run (on my Ubuntu Linux system) I get these errors, the clearest of which seems to be reporting an I/O error:

Does anyone know how I might go about diagnosing the problem here, and if at all possible recovering the data on this hard drive?

Update:

I decided to follow these instructions about recovering a bad superblock from a corrupted drive. That involved running the command . When I did that, I go the following error. I'm not sure how to answer that:

When I answered yes, I just got another for the next block (164868). Is this a bad sign? Is there a next step I should take from here perhaps?

Update 2:

It looks to me as though the disk is really far gone. I ran ddrescue and here were the results:

Is this a lost cause?

Unable to mount 1TB USB external HDD - Error

I'm getting an error when I plug in my 1TB USB external HDD, the weird thing about this is that it was working fine before and I've been using it for about a couple of months now. yesterday I compressed one of the folders which had about 120GB of data but the compression failed after an hour and I decided to unmount the drive and shut everything down.

Today when I tried to plug in the drive I got the following error:

Error mounting: mount: wrong fs type, bad option, bad superblock on /dev/sdc, missing codepage or helper program, or other error In some cases useful info is found in syslog - try dmesg

Replies

 

Same thing, but I didn't upgrade. I'm using a fresh M1 Macbook Air and it simply won't mount anything external. I can see it. It just says "not mounted"...

 

Same thing for me. I can plug it into my iPad without any issue, so it is definitely not a problem with the HDD. It seems like it may be a bug on 11.0.1

 

I have the same issue. External USB drive's that still mount in Catalina don't mount in already-running Big Sur. But if they're plugged in when Big Sur starts up, they'll mount OK.

 

Well, please disregard my post of a few hours ago. I shut down, started up, and now external USB drives are mounting fine. Beats me. Sorry if I'm in anyway out of line ... I'm new here so thanks in advance for slack.

 

I have similar issues with external USB Flash drives on Big Sur 11.0.1 (MacBook Pro (Retina, 15-inch, Mid 2015)). After plugging in USB drive I can't find it in Finder but it still can be founded under /Volumes folder. Open Finder -> Go -> Go to folder /Volumes (shortcut SHIFT + CMD + G). I hope it'll help.

 

Similar issue here too. When plugging in either usbC or usb3 external drives - my experience shows this is a flip of the coin whether Big Sur recognizes and mounts the drive or not. I think particularly that the exFAT partition format type has something to do with this issue. Apple's Disk Utility also has a hard time displaying what the actual formatted partition is. For instance, I took an Apple drive over to my Ubuntu Linux machine, erased the drive and repartitioned it as exFAT, removed it and plugged it into my MacBook Pro on a USB adapter and it didn't recognize the disk even after several unplugging and replugging attempts. So I rebooted. It saw the external drive, but showed it still as an Apple Journaled APFS partioned drive. That's odd I thought, so I unmounted it, removed it and plugged it back into my Ubuntu Linux machine. Lo and behold it was exFAT not APFS. What's going on with Apple's Big Sur? Hard to say, but it looks and feels like a bug.

 

I'm having this same issue with my Macbook Pro (2019). I've tired restarting. I've tried repairing disk but it will not mount. I'm not sure what the cause is. I have my music library on it so I don't want to format it and lose it. It's currently in Fat32. I'm unsure why Big Sur won't read it as my computer was able to read it on Catalina when I first got it.

 

I Have similar issue, i can see my external drives but if i transfer files to or from the external drive it starts slow and stops and in some inctents iit exit it by it self. i started seeing this after the update 11.1- Please help.

 

I'm also seeing this issue on an M1 MBP. I'm able to go into Disk Utility and mount my external drives from there, and I'm prompted to enter my drives encryption password. And regardless of whether I check the box to remember or not, it doesn't remember and mount them again after a reboot. Not sure of the cause here, but I'm (in my head anyway) attributing my slow Finder beachball issues to whatever is causing this issue.

 

I have a MacBook Pro 2019, My seagate 1TB hard drive would not mount for a while..... I have a thunderbolt -usb adaptor connected and thought it might have originally been a poor connection due to cable, after restarting my Mac in safe mode and restarting etc etc nothing appeared to work. but after leaving the device connected for approx 20mins the hard drive and all its files have appeared. just thought id share this anyway.

 

Macbook Pro, M1, Big Sur. Attempted to transfer file from win10 pc to mac via flash drive. Flash drive mounted but files not visible, running properties indicated files were present. Inserted other flash drives from pc, the drive mounted but files not visible.

 

Hi There,

I was having the same issue with my external lacie G drive not mounting but was visible in Disk utility.

I tried all sorts of things and the one that worked for me was to zap the P Ram.

I am on MacBook Pro, so restart the Mac hold shift+control+option+power button 10 secs. Once I had done this I logged back in and boom the drive mounted. I hope this helps.

 

I have been having the same problems not just with big sur but with Catalina also I have lost a lot of important work and file and more than one flash drive which has cost me a lot.
but what is bothering me is how Apple have not said anything, they keep bringing out new versions before making sure they are fit for use.
they need to work on the issues that are happening before moving forward.
i have spend thousands on there Products only for them to let me down and cost me more.
this is a joke.
Apple are proving to be unreliable.

 

I have same problems with new MacBook pro 16'. No HDD nor SSD. They worked totally fine with old MB pro 13' with Catalina.

 

in order to get big sur to recognize your USB drive & show it on the desktop
  • Open Disk Utility

  • Choose "Show All Devices" from the View menu

  • Select the destination drive hardware (above the existing volume)

  • Click Erase

  • Choose the "GUID" partition scheme (2nd pop-up), THEN "APFS" formatting (1st pop-up) and name appropriately

  • Click Erase


if you have files on the USB drive you should be able to open them with an app & then save them, if they are essential, before you erase.

SMART Error for HDD, cannot mount drive

In Ubuntu (Linux) you couldn't mount the drive, but it sounds like you gave up too easily, there's a world of difference between "filesystem inconsistencies / wasn't cleanly unmounted" that won't let an automatic mount, and "not recognized as a device, can't read a single sector" that you can read data & work with. Mounting can fail if windows is in "fast shutdown" mode, or there's filesystem errors, so it's definitely not a show stopper that it couldn't mount.

If a new appears then you can read (or at least attempt to read) the drive, and read SMART info & attempt tests. Since it's a USB drive, after connecting it a new device (X could be any letter) should show up, see & /var/log/syslog for info (especially errors if there's no new device - without a device it might not be possible to read anything, or even harder to try).

If you can read anything from the device then it's looking much better that (in package named gddrescue) or / or something can get some data. Probably need root rights too, with . Like or .

  • A very basic "read a little" with would be:

    reading the first M (=1024*1024 bytes) from the drive, and

    • is how many bytes to read/write in each "block"
    • is the number of "blocks" to take
    • skip N ibs-sized blocks at start of input
    • Just don't mix up the , it will overwrite almost anything!
  • To skip 1000M's and then read 1M, use:

See https://wiki.archlinux.org/index.php/file_recovery and/or https://help.ubuntu.com/community/DataRecovery for more info, it can be involved. gddrescue has a great (but dry) GNU ddrescue Manual too, and search the web for lots more info.

& are the easiest to use IMO, I don't even bother with foremost or scalpel. Their homepages have good guides, see TestDisk's & TestDisk Step By Step and PhotoRec's & PhotoRec Step By Step. If testdisk can read the existing files, then copying them might be fairly easy, photorec doesn't save original filenames or directory structure.

Sometimes errors will show up when attempting reads & they might fail, error messages will probably flood & /var/log/syslog then, I like to keep a terminal open running &/or to see new errors as they arrive. If you've got the space on another device, making a whole copy with gddrescue might be a good idea, it tries to skip over error sectors and read all the "good stuff" first, then try errors again later (or read "backwards", jump around, etc).


You could use (in the smartmontools package) to read the SMART data & find out what it's errors are, even run new tests (but if the drive is failing, more tests could run down the clock on it's remaining life, so a backup first might be prudent). Here's my "notes" on :

Commands to generate reports:

  • - prints all SMART info
  • - prints all SMART and non-SMART info

If you're tracking changes, you could run a test every so often, saving it to a date-named file with:

To just get the "stats":

sudo smartctl -A /dev/sdX > $(date +"%Y-%m-%d_%H.%M")-sdX-smart-A

Tests

Use the option where TYPE is one of:

short maybe ~2min
conveyance maybe ~5m
long maybe ~55m
offline maybe ~73m (4380s)
[times are examples from an old drive]

But not all drives support all tests.

The option has a "Self-test execution status:" line that tells the current test's % remaining (if a test is running).

To see status could use:

Hard disk drive

Data storage device

"Hard drive" redirects here. For other uses, see Hard Drive (disambiguation).

IBM 350 RAMAC.jpg

Partially disassembled IBM 350 (RAMAC)

Date inventedDecember 24, 1954; 67 years ago (1954-12-24)[a]
Invented byIBM team led by Rey Johnson
Internals of a 2.5-inch laptop hard disk drive
A disassembled and labeled 1997 HDD lying atop a mirror
An overview of how HDDs work

A hard disk drive (HDD), hard disk, hard drive, or fixed disk[b] is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage with one or more rigid rapidly rotating platters coated with magnetic material. The platters are paired with magnetic heads, usually arranged on a moving actuator arm, which read and write data to the platter surfaces.[2] Data is accessed in a random-access manner, meaning that individual blocks of data can be stored and retrieved in any order. HDDs are a type of non-volatile storage, retaining stored data when powered off.[3][4][5] Modern HDDs are typically in the form of a small rectangular box.

Introduced by IBM in 1956,[6] HDDs were the dominant secondary storage device for general-purpose computers beginning in the early 1960s. HDDs maintained this position into the modern era of servers and personal computers, though personal computing devices produced in large volume, like cell phones and tablets, rely on flash memory storage devices. More than 224 companies have produced HDDs historically, though after extensive industry consolidation most units are manufactured by Seagate, Toshiba, and Western Digital. HDDs dominate the volume of storage produced (exabytes per year) for servers. Though production is growing slowly (by exabytes shipped[7]), sales revenues and unit shipments are declining because solid-state drives (SSDs) have higher data-transfer rates, higher areal storage density, somewhat better reliability,[8][9] and much lower latency and access times.[10][11][12][13]

The revenues for SSDs, most of which use NAND flash memory, slightly exceeded those for HDDs in 2018.[14] Flash storage products had more than twice the revenue of hard disk drives as of 2017[update].[15] Though SSDs have four to nine times higher cost per bit,[16][17] they are replacing HDDs in applications where speed, power consumption, small size, high capacity and durability are important.[12][13] As of 2019[update], the cost per bit of SSDs is falling, and the price premium over HDDs has narrowed.[17]

The primary characteristics of an HDD are its capacity and performance. Capacity is specified in unit prefixes corresponding to powers of 1000: a 1-terabyte (TB) drive has a capacity of 1,000 gigabytes (GB; where 1 gigabyte = 1 billion (109) bytes). Typically, some of an HDD's capacity is unavailable to the user because it is used by the file system and the computer operating system, and possibly inbuilt redundancy for error correction and recovery. There can be confusion regarding storage capacity, since capacities are stated in decimal gigabytes (powers of 1000) by HDD manufacturers, whereas the most commonly used operating systems report capacities in powers of 1024, which results in a smaller number than advertised. Performance is specified as the time required to move the heads to a track or cylinder (average access time), the time it takes for the desired sector to move under the head (average latency, which is a function of the physical rotational speed in revolutions per minute), and finally the speed at which the data is transmitted (data rate).

The two most common form factors for modern HDDs are 3.5-inch, for desktop computers, and 2.5-inch, primarily for laptops. HDDs are connected to systems by standard interface cables such as PATA (Parallel ATA), SATA (Serial ATA), USB or SAS (Serial Attached SCSI) cables.

History[edit]

Main article: History of hard disk drives

Video of modern HDD operation (cover removed)

The first production IBM hard disk drive, the 350 disk storage, shipped in 1957 as a component of the IBM 305 RAMAC system. It was approximately the size of two medium-sized refrigerators and stored five million six-bit characters (3.75 megabytes)[18] on a stack of 52 disks (100 surfaces used).[35] The 350 had a single arm with two read/write heads, one facing up and the other down, that moved both horizontally between a pair of adjacent platters and vertically from one pair of platters to a second set.[36][37][38] Variants of the IBM 350 were the IBM 355, IBM 7300 and IBM 1405.

In 1961 IBM announced, and in 1962 shipped, the IBM 1301 disk storage unit,[39] which superseded the IBM 350 and similar drives. The 1301 consisted of one (for Model 1) or two (for model 2) modules, each containing 25 platters, each platter about 1⁄8-inch (3.2 mm) thick and 24 inches (610 mm) in diameter.[40] While the earlier IBM disk drives used only two read/write heads per arm, the 1301 used an array of 48[e] heads (comb), each array moving horizontally as a single unit, one head per surface used. Cylinder-mode read/write operations were supported, and the heads flew about 250 micro-inches (about 6 µm) above the platter surface. Motion of the head array depended upon a binary adder system of hydraulic actuators which assured repeatable positioning. The 1301 cabinet was about the size of three home refrigerators placed side by side, storing the equivalent of about 21 million eight-bit bytes per module. Access time was about a quarter of a second.

Also in 1962, IBM introduced the model 1311 disk drive, which was about the size of a washing machine and stored two million characters on a removable disk pack. Users could buy additional packs and interchange them as needed, much like reels of magnetic tape. Later models of removable pack drives, from IBM and others, became the norm in most computer installations and reached capacities of 300 megabytes by the early 1980s. Non-removable HDDs were called "fixed disk" drives.

In 1963 IBM introduced the 1302,[41] with twice the track capacity and twice as many tracks per cylinder as the 1301. The 1302 had one (for Model 1) or two (for Model 2) modules, each containing a separate comb for the first 250 tracks and the last 250 tracks.

Some high-performance HDDs were manufactured with one head per track, e.g., Burroughs B-475 in 1964, IBM 2305 in 1970, so that no time was lost physically moving the heads to a track and the only latency was the time for the desired block of data to rotate into position under the head.[42] Known as fixed-head or head-per-track disk drives, they were very expensive and are no longer in production.[43]

In 1973, IBM introduced a new type of HDD code-named "Winchester". Its primary distinguishing feature was that the disk heads were not withdrawn completely from the stack of disk platters when the drive was powered down. Instead, the heads were allowed to "land" on a special area of the disk surface upon spin-down, "taking off" again when the disk was later powered on. This greatly reduced the cost of the head actuator mechanism, but precluded removing just the disks from the drive as was done with the disk packs of the day. Instead, the first models of "Winchester technology" drives featured a removable disk module, which included both the disk pack and the head assembly, leaving the actuator motor in the drive upon removal. Later "Winchester" drives abandoned the removable media concept and returned to non-removable platters.

In 1974 IBM introduced the swinging arm actuator, made feasible because the Winchester recording heads function well when skewed to the recorded tracks. The simple design of the IBM GV (Gulliver) drive,[44] invented at IBM's UK Hursley Labs, became IBM's most licensed electro-mechanical invention[45] of all time, the actuator and filtration system being adopted in the 1980s eventually for all HDDs, and still universal nearly 40 years and 10 Billion arms later.

Like the first removable pack drive, the first "Winchester" drives used platters 14 inches (360 mm) in diameter. In 1978 IBM introduced a swing arm drive, the IBM 0680 (Piccolo), with eight inch platters, exploring the possibility that smaller platters might offer advantages. Other eight inch drives followed, then 5+1⁄4 in (130 mm) drives, sized to replace the contemporary floppy disk drives. The latter were primarily intended for the then fledgling personal computer (PC) market.

Over time, as recording densities were greatly increased, further reductions in disk diameter to 3.5" and 2.5" were found to be optimum. Powerful rare earth magnet materials became affordable during this period, and were complementary to the swing arm actuator design to make possible the compact form factors of modern HDDs.

As the 1980s began, HDDs were a rare and very expensive additional feature in PCs, but by the late 1980s their cost had been reduced to the point where they were standard on all but the cheapest computers.

Most HDDs in the early 1980s were sold to PC end users as an external, add-on subsystem. The subsystem was not sold under the drive manufacturer's name but under the subsystem manufacturer's name such as Corvus Systems and Tallgrass Technologies, or under the PC system manufacturer's name such as the Apple ProFile. The IBM PC/XT in 1983 included an internal 10 MB HDD, and soon thereafter internal HDDs proliferated on personal computers.

External HDDs remained popular for much longer on the Apple Macintosh. Many Macintosh computers made between 1986 and 1998 featured a SCSI port on the back, making external expansion simple. Older compact Macintosh computers did not have user-accessible hard drive bays (indeed, the Macintosh 128K, Macintosh 512K, and Macintosh Plus did not feature a hard drive bay at all), so on those models external SCSI disks were the only reasonable option for expanding upon any internal storage.

HDD improvements have been driven by increasing areal density, listed in the table above. Applications expanded through the 2000s, from the mainframe computers of the late 1950s to most mass storage applications including computers and consumer applications such as storage of entertainment content.

In the 2000s and 2010s, NAND began supplanting HDDs in applications requiring portability or high performance. NAND performance is improving faster than HDDs, and applications for HDDs are eroding. In 2018, the largest hard drive had a capacity of 15 TB, while the largest capacity SSD had a capacity of 100 TB.[46] As of 2018[update], HDDs were forecast to reach 100 TB capacities around 2025,[47] but as of 2019[update] the expected pace of improvement was pared back to 50 TB by 2026.[48] Smaller form factors, 1.8-inches and below, were discontinued around 2010. The cost of solid-state storage (NAND), represented by Moore's law, is improving faster than HDDs. NAND has a higher price elasticity of demand than HDDs, and this drives market growth.[49] During the late 2000s and 2010s, the product life cycle of HDDs entered a mature phase, and slowing sales may indicate the onset of the declining phase.[50]

The 2011 Thailand floods damaged the manufacturing plants and impacted hard disk drive cost adversely between 2011 and 2013.[51]

In 2019, Western Digital closed its last Malaysian HDD factory due to decreasing demand, to focus on SSD production.[52] All three remaining HDD manufacturers have had decreasing demand for their HDDs since 2014.[53]

Technology[edit]

Magnetic recording[edit]

See also: Magnetic storage

A modern HDD records data by magnetizing a thin film of ferromagnetic material[f] on both sides of a disk. Sequential changes in the direction of magnetization represent binary data bits. The data is read from the disk by detecting the transitions in magnetization. User data is encoded using an encoding scheme, such as run-length limited encoding,[g] which determines how the data is represented by the magnetic transitions.

A typical HDD design consists of a spindle that holds flat circular disks, called platters, which hold the recorded data. The platters are made from a non-magnetic material, usually aluminum alloy, glass, or ceramic. They are coated with a shallow layer of magnetic material typically 10–20 nm in depth, with an outer layer of carbon for protection.[55][56][57] For reference, a standard piece of copy paper is 0.07–0.18 mm (70,000–180,000 nm)[58] thick.

Destroyed hard disk, glass platter visible
Diagram labeling the major components of a computer HDD
Recording of single magnetisations of bits on a 200 MB HDD-platter (recording made visible using CMOS-MagView).[59]

The platters in contemporary HDDs are spun at speeds varying from 4,200 RPM in energy-efficient portable devices, to 15,000 rpm for high-performance servers.[60] The first HDDs spun at 1,200 rpm[6] and, for many years, 3,600 rpm was the norm.[61] As of November 2019[update], the platters in most consumer-grade HDDs spin at 5,400 or 7,200 RPM.

Information is written to and read from a platter as it rotates past devices called read-and-write heads that are positioned to operate very close to the magnetic surface, with their flying height often in the range of tens of nanometers. The read-and-write head is used to detect and modify the magnetization of the material passing immediately under it.

In modern drives, there is one head for each magnetic platter surface on the spindle, mounted on a common arm. An actuator arm (or access arm) moves the heads on an arc (roughly radially) across the platters as they spin, allowing each head to access almost the entire surface of the platter as it spins. The arm is moved using a voice coil actuator or in some older designs a stepper motor. Early hard disk drives wrote data at some constant bits per second, resulting in all tracks having the same amount of data per track but modern drives (since the 1990s) use zone bit recording – increasing the write speed from inner to outer zone and thereby storing more data per track in the outer zones.

In modern drives, the small size of the magnetic regions creates the danger that their magnetic state might be lost because of thermal effects⁠ ⁠— thermally induced magnetic instability which is commonly known as the "superparamagnetic limit". To counter this, the platters are coated with two parallel magnetic layers, separated by a three-atom layer of the non-magnetic element ruthenium, and the two layers are magnetized in opposite orientation, thus reinforcing each other.[62] Another technology used to overcome thermal effects to allow greater recording densities is perpendicular recording, first shipped in 2005,[63] and as of 2007[update] used in certain HDDs.[64][65][66]

In 2004, a higher-density recording media was introduced, consisting of coupled soft and hard magnetic layers. So-called exchange spring media magnetic storage technology, also known as exchange coupled composite media, allows good writability due to the write-assist nature of the soft layer. However, the thermal stability is determined only by the hardest layer and not influenced by the soft layer.[67][68]

Components[edit]

An HDD with disks and motor hub removed, exposing copper-colored stator coils surrounding a bearing in the center of the spindle motor. The orange stripe along the side of the arm is a thin printed-circuit cable, the spindle bearing is in the center and the actuator is in the upper left.

A typical HDD has two electric motors: a spindle motor that spins the disks and an actuator (motor) that positions the read/write head assembly across the spinning disks. The disk motor has an external rotor attached to the disks; the stator windings are fixed in place. Opposite the actuator at the end of the head support arm is the read-write head; thin printed-circuit cables connect the read-write heads to amplifier electronics mounted at the pivot of the actuator. The head support arm is very light, but also stiff; in modern drives, acceleration at the head reaches 550 g.

Head stack with an actuator coil on the left and read/write heads on the right

The actuator is a permanent magnet and moving coil motor that swings the heads to the desired position. A metal plate supports a squat neodymium-iron-boron (NIB) high-flux magnet. Beneath this plate is the moving coil, often referred to as the voice coil by analogy to the coil in loudspeakers, which is attached to the actuator hub, and beneath that is a second NIB magnet, mounted on the bottom plate of the motor (some drives have only one magnet).

The voice coil itself is shaped rather like an arrowhead and is made of doubly coated copper magnet wire. The inner layer is insulation, and the outer is thermoplastic, which bonds the coil together after it is wound on a form, making it self-supporting. The portions of the coil along the two sides of the arrowhead (which point to the center of the actuator bearing) then interact with the magnetic field of the fixed magnet. Current flowing radially outward along one side of the arrowhead and radially inward on the other produces the tangential force. If the magnetic field were uniform, each side would generate opposing forces that would cancel each other out. Therefore, the surface of the magnet is half north pole and half south pole, with the radial dividing line in the middle, causing the two sides of the coil to see opposite magnetic fields and produce forces that add instead of canceling. Currents along the top and bottom of the coil produce radial forces that do not rotate the head.

The HDD's electronics control the movement of the actuator and the rotation of the disk and perform reads and writes on demand from the disk controller. Feedback of the drive electronics is accomplished by means of special segments of the disk dedicated to servo feedback. These are either complete concentric circles (in the case of dedicated servo technology) or segments interspersed with real data (in the case of embedded servo technology). The servo feedback optimizes the signal-to-noise ratio of the GMR sensors by adjusting the voice coil of the actuated arm. The spinning of the disk also uses a servo motor. Modern disk firmware is capable of scheduling reads and writes efficiently on the platter surfaces and remapping sectors of the media that have failed.

Error rates and handling[edit]

Modern drives make extensive use of error correction codes (ECCs), particularly Reed–Solomon error correction. These techniques store extra bits, determined by mathematical formulas, for each block of data; the extra bits allow many errors to be corrected invisibly. The extra bits themselves take up space on the HDD, but allow higher recording densities to be employed without causing uncorrectable errors, resulting in much larger storage capacity.[69] For example, a typical 1 TB hard disk with 512-byte sectors provides additional capacity of about 93 GB for the ECC data.[70]

In the newest drives, as of 2009[update],[71]low-density parity-check codes (LDPC) were supplanting Reed–Solomon; LDPC codes enable performance close to the Shannon Limit and thus provide the highest storage density available.[71][72]

Typical hard disk drives attempt to "remap" the data in a physical sector that is failing to a spare physical sector provided by the drive's "spare sector pool" (also called "reserve pool"),[73] while relying on the ECC to recover stored data while the number of errors in a bad sector is still low enough. The S.M.A.R.T (Self-Monitoring, Analysis and Reporting Technology) feature counts the total number of errors in the entire HDD fixed by ECC (although not on all hard drives as the related S.M.A.R.T attributes "Hardware ECC Recovered" and "Soft ECC Correction" are not consistently supported), and the total number of performed sector remappings, as the occurrence of many such errors may predict an HDD failure.

The "No-ID Format", developed by IBM in the mid-1990s, contains information about which sectors are bad and where remapped sectors have been located.[74]

Only a tiny fraction of the detected errors end up as not correctable. Examples of specified uncorrected bit read error rates include:

  • 2013 specifications for enterprise SAS disk drives state the error rate to be one uncorrected bit read error in every 1016 bits read,[75][76]
  • 2018 specifications for consumer SATA hard drives state the error rate to be one uncorrected bit read error in every 1014 bits.[77][78]

Within a given manufacturers model the uncorrected bit error rate is typically the same regardless of capacity of the drive.[75][76][77][78]

The worst type of errors are silent data corruptions which are errors undetected by the disk firmware or the host operating system; some of these errors may be caused by hard disk drive malfunctions while others originate elsewhere in the connection between the drive and the host.[79]

Development[edit]

Leading-edge hard disk drive areal densities from 1956 through 2009 compared to Moore's law. By 2016, progress had slowed significantly below the extrapolated density trend.[80]

The rate of areal density advancement was similar to Moore's law (doubling every two years) through 2010: 60% per year during 1988–1996, 100% during 1996–2003 and 30% during 2003–2010.[81] Speaking in 1997, Gordon Moore called the increase "flabbergasting",[82] while observing later that growth cannot continue forever.[83] Price improvement decelerated to −12% per year during 2010–2017,[84] as the growth of areal density slowed. The rate of advancement for areal density slowed to 10% per year during 2010–2016,[85] and there was difficulty in migrating from perpendicular recording to newer technologies.[86]

As bit cell size decreases, more data can be put onto a single drive platter. In 2013, a production desktop 3 TB HDD (with four platters) would have had an areal density of about 500 Gbit/in2 which would have amounted to a bit cell comprising about 18 magnetic grains (11 by 1.6 grains).[87] Since the mid-2000s areal density progress has been challenged by a superparamagnetic trilemma involving grain size, grain magnetic strength and ability of the head to write.[88] In order to maintain acceptable signal to noise smaller grains are required; smaller grains may self-reverse (electrothermal instability) unless their magnetic strength is increased, but known write head materials are unable to generate a strong enough magnetic field sufficient to write the medium in the increasingly smaller space taken by grains.

Magnetic storage technologies are being developed to address this trilemma, and compete with flash memory–based solid-state drives (SSDs). In 2013, Seagate introduced shingled magnetic recording (SMR),[89] intended as something of a "stopgap" technology between PMR and Seagate's intended successor heat-assisted magnetic recording (HAMR), SMR utilises overlapping tracks for increased data density, at the cost of design complexity and lower data access speeds (particularly write speeds and random access 4k speeds).[90][91]

By contrast, HGST (now part of Western Digital) focused on developing ways to seal helium-filled drives instead of the usual filtered air. Since turbulence and friction are reduced, higher areal densities can be achieved due to using a smaller track width, and the energy dissipated due to friction is lower as well, resulting in a lower power draw. Furthermore, more platters can be fit into the same enclosure space, although helium gas is notoriously difficult to prevent escaping.[92] Thus, helium drives are completely sealed and do not have a breather port, unlike their air-filled counterparts.

Other recording technologies are either under research or have been commercially implemented to increase areal density, including Seagate's heat-assisted magnetic recording (HAMR). HAMR requires a different architecture with redesigned media and read/write heads, new lasers, and new near-field optical transducers.[93] HAMR is expected to ship commercially in late 2020 or 2021.[94][95] Technical issues delayed the introduction of HAMR by a decade, from earlier projections of 2009,[96] 2015,[97] 2016,[98] and the first half of 2019. Some drives have adopted dual independent actuator arms to increase read/write speeds and compete with SSDs.[99] HAMR's planned successor, bit-patterned recording (BPR),[100] has been removed from the roadmaps of Western Digital and Seagate.[101] Western Digital's microwave-assisted magnetic recording (MAMR),[102][103] also referred to as energy-assisted magnetic recording (EAMR), was sampled in 2020, with the first EAMR drive, the Ultrastar HC550, shipping in late 2020.[104][105][106]Two-dimensional magnetic recording (TDMR)[87][107] and "current perpendicular to plane" giant magnetoresistance (CPP/GMR) heads have appeared in research papers.[108][109][110] A 3D-actuated vacuum drive (3DHD) concept has been proposed.[111]

The rate of areal density growth had dropped below the historical Moore's law rate of 40% per year by 2016.[80] Depending upon assumptions on feasibility and timing of these technologies, Seagate forecasts that areal density will grow 20% per year during 2020–2034.[48]

Capacity[edit]

The highest-capacity HDDs shipping commercially in 2022 are 20 TB.[112][113]

The capacity of a hard disk drive, as reported by an operating system to the end user, is smaller than the amount stated by the manufacturer for several reasons, e.g., the operating system using some space, use of some space for data redundancy, space use for file system structures. Also the difference in capacity reported in SI decimal prefixed units vs. binary prefixes can lead to a false impression of missing capacity.

Calculation[edit]

Modern hard disk drives appear to their host controller as a contiguous set of logical blocks, and the gross drive capacity is calculated by multiplying the number of blocks by the block size. This information is available from the manufacturer's product specification, and from the drive itself through use of operating system functions that invoke low-level drive commands.[114][115]

Older IBM and compatible drives, e.g., IBM 3390, using the CKD record format have variable length records; such drive capacity calculations must take into account the characteristics of the records. Some newer DASD simulate CKD, and the same capacity formulae apply.

The gross capacity of older sector-oriented HDDs is calculated as the product of the number of cylinders per recording zone, the number of bytes per sector (most commonly 512), and the count of zones of the drive.[citation needed] Some modern SATA drives also report cylinder-head-sector (CHS) capacities, but these are not physical parameters because the reported values are constrained by historic operating system interfaces. The C/H/S scheme has been replaced by logical block addressing (LBA), a simple linear addressing scheme that locates blocks by an integer index, which starts at LBA 0 for the first block and increments thereafter.[116] When using the C/H/S method to describe modern large drives, the number of heads is often set to 64, although a typical modern hard disk drive has between one and four platters. In modern HDDs, spare capacity for defect management is not included in the published capacity; however, in many early HDDs a certain number of sectors were reserved as spares, thereby reducing the capacity available to the operating system. Furthermore, many HDDs store their firmware in a reserved service zone, which is typically not accessible by the user, and is not included in the capacity calculation.

For RAID subsystems, data integrity and fault-tolerance requirements also reduce the realized capacity. For example, a RAID 1 array has about half the total capacity as a result of data mirroring, while a RAID 5 array with n drives loses 1/n of capacity (which equals to the capacity of a single drive) due to storing parity information. RAID subsystems are multiple drives that appear to be one drive or more drives to the user, but provide fault tolerance. Most RAID vendors use checksums to improve data integrity at the block level. Some vendors design systems using HDDs with sectors of 520 bytes to contain 512 bytes of user data and eight checksum bytes, or by using separate 512-byte sectors for the checksum data.[117]

Some systems may use hidden partitions for system recovery, reducing the capacity available to the end user without knowledge of special disk partitioning utilities like diskpart in Windows.[citation needed]

Formatting[edit]

Main article: Disk formatting

Data is stored on a hard drive in a series of logical blocks. Each block is delimited by markers identifying its start and end, error detecting and correcting information, and space between blocks to allow for minor timing variations. These blocks often contained 512 bytes of usable data, but other sizes have been used. As drive density increased, an initiative known as Advanced Format extended the block size to 4096 bytes of usable data, with a resulting significant reduction in the amount of disk space used for block headers, error checking data, and spacing.

The process of initializing these logical blocks on the physical disk platters is called low-level formatting, which is usually performed at the factory and is not normally changed in the field.[118]High-level formatting writes data structures used by the operating system to organize data files on the disk. This includes writing partition and file system structures into selected logical blocks. For example, some of the disk space will be used to hold a directory of disk file names and a list of logical blocks associated with a particular file.

Examples of partition mapping scheme include Master boot record (MBR) and GUID Partition Table (GPT). Examples of data structures stored on disk to retrieve files include the File Allocation Table (FAT) in the DOS file system and inodes in many UNIX file systems, as well as other operating system data structures (also known as metadata). As a consequence, not all the space on an HDD is available for user files, but this system overhead is usually small compared with user data.

Units[edit]

See also: Binary prefix § disk drives

Capacity advertised by manufacturers[h]Capacity expected by some consumers[i]Reported capacity
Windows[i]macOS ver 10.6+[h]
With prefix Bytes Bytes Diff.
100 GB100,000,000,000 107,374,182,400 7.37% 93.1 GB 100 GB
1 TB1,000,000,000,000 1,099,511,627,776 9.95% 931 GB 1,000 GB, 1,000,000 MB

In the early days of computing the total capacity of HDDs was specified in 7 to 9 decimal digits frequently truncated with the idiom millions.[121][41] By the 1970s, the total capacity of HDDs was given by manufacturers using SI decimal prefixes such as megabytes (1 MB = 1,000,000 bytes), gigabytes (1 GB = 1,000,000,000 bytes) and terabytes (1 TB = 1,000,000,000,000 bytes).[119][122][123][124] However, capacities of memory are usually quoted using a binary interpretation of the prefixes, i.e. using powers of 1024 instead of 1000.

Software reports hard disk drive or memory capacity in different forms using either decimal or binary prefixes. The Microsoft Windows family of operating systems uses the binary convention when reporting storage capacity, so an HDD offered by its manufacturer as a 1 TB drive is reported by these operating systems as a 931 GB HDD. Mac OS X 10.6 ("Snow Leopard") uses decimal convention when reporting HDD capacity.[125] The default behavior of the dfcommand-line utility on Linux is to report the HDD capacity as a number of 1024-byte units.[126]

The difference between the decimal and binary prefix interpretation caused some consumer confusion and led to class action suits against HDD manufacturers. The plaintiffs argued that the use of decimal prefixes effectively misled consumers while the defendants denied any wrongdoing or liability, asserting that their marketing and advertising complied in all respects with the law and that no class member sustained any damages or injuries.[127][128][129]

Price evolution[edit]

HDD price per byte decreased at the rate of 40% per year during 1988–1996, 51% per year during 1996–2003 and 34% per year during 2003–2010.[28][81] The price decrease slowed down to 13% per year during 2011–2014, as areal density increase slowed and the 2011 Thailand floods damaged manufacturing facilities[86] and have held at 11% per year during 2010–2017.[130]

The Federal Reserve Board has published a quality-adjusted price index for large-scale enterprise storage systems including three or more enterprise HDDs and associated controllers, racks and cables. Prices for these large-scale storage systems decreased at the rate of 30% per year during 2004–2009 and 22% per year during 2009–2014.[81]

Form factors[edit]

Main article: List of disk drive form factors

8-, 5.25-, 3.5-, 2.5-, 1.8- and 1-inch HDDs, together with a ruler to show the size of platters and read-write heads
A newer 2.5-inch (63.5 mm) 6,495 MB HDD compared to an older 5.25-inch full-height 110 MB HDD

IBM's first hard disk drive, the IBM 350, used a stack of fifty 24-inch platters, stored 3.75 MB of data (approximately the size of one modern digital picture), and was of a size comparable to two large refrigerators. In 1962, IBM introduced its model 1311 disk, which used six 14-inch (nominal size) platters in a removable pack and was roughly the size of a washing machine. This became a standard platter size for many years, used also by other manufacturers.[131] The IBM 2314 used platters of the same size in an eleven-high pack and introduced the "drive in a drawer" layout. sometimes called the"pizza oven", although the "drawer" was not the complete drive. Into the 1970s HDDs were offered in standalone cabinets of varying dimensions containing from one to four HDDs.

Beginning in the late 1960s drives were offered that fit entirely into a chassis that would mount in a 19-inch rack. Digital's RK05 and RL01 were early examples using single 14-inch platters in removable packs, the entire drive fitting in a 10.5-inch-high rack space (six rack units). In the mid-to-late 1980s the similarly sized Fujitsu Eagle, which used (coincidentally) 10.5-inch platters, was a popular product.

With increasing sales of microcomputers having built in floppy-disk drives (FDDs), HDDs that would fit to the FDD mountings became desirable. Starting with the Shugart Associates SA1000, HDD form factors initially followed those of 8-inch, 5¼-inch, and 3½-inch floppy disk drives. Although referred to by these nominal sizes, the actual sizes for those three drives respectively are 9.5", 5.75" and 4" wide. Because there were no smaller floppy disk drives, smaller HDD form factors such as 2½-inch drives (actually 2.75" wide) developed from product offerings or industry standards.

As of 2019[update], 2½-inch and 3½-inch hard disks are the most popular sizes. By 2009, all manufacturers had discontinued the development of new products for the 1.3-inch, 1-inch and 0.85-inch form factors due to falling prices of flash memory,[132][133] which has no moving parts. While nominal sizes are in inches, actual dimensions are specified in millimeters.

Performance characteristics[edit]

Main article: Hard disk drive performance characteristics

The factors that limit the time to access the data on an HDD are mostly related to the mechanical nature of the rotating disks and moving heads, including:

  • Seek time is a measure of how long it takes the head assembly to travel to the track of the disk that contains data.
  • Rotational latency is incurred because the desired disk sector may not be directly under the head when data transfer is requested. Average rotational latency is shown in the table, based on the statistical relation that the average latency is one-half the rotational period.
  • The bit rate or data transfer rate (once the head is in the right position) creates delay which is a function of the number of blocks transferred; typically relatively small, but can be quite long with the transfer of large contiguous files.

Delay may also occur if the drive disks are stopped to save energy.

Defragmentation is a procedure used to minimize delay in retrieving data by moving related items to physically proximate areas on the disk.[134] Some computer operating systems perform defragmentation automatically. Although automatic defragmentation is intended to reduce access delays, performance will be temporarily reduced while the procedure is in progress.[135]

Time to access data can be improved by increasing rotational speed (thus reducing latency) or by reducing the time spent seeking. Increasing areal density increases throughput by increasing data rate and by increasing the amount of data under a set of heads, thereby potentially reducing seek activity for a given amount of data. The time to access data has not kept up with throughput increases, which themselves have not kept up with growth in bit density and storage capacity.

Latency[edit]

Rotational speed
[rpm]
Average rotational latency
[ms]
15,000 2
10,000 3
7,200 4.16
5,400 5.55
4,800 6.25

Data transfer rate[edit]

As of 2010[update], a typical 7,200-rpm desktop HDD has a sustained "disk-to-buffer" data transfer rate up to 1,030 Mbit/s.[136] This rate depends on the track location; the rate is higher for data on the outer tracks (where there are more data sectors per rotation) and lower toward the inner tracks (where there are fewer data sectors per rotation); and is generally somewhat higher for 10,000-rpm drives. A current widely used standard for the "buffer-to-computer" interface is 3.0 Gbit/s SATA, which can send about 300 megabyte/s (10-bit encoding) from the buffer to the computer, and thus is still comfortably ahead of today's disk-to-buffer transfer rates. Data transfer rate (read/write) can be measured by writing a large file to disk using special file generator tools, then reading back the file. Transfer rate can be influenced by file system fragmentation and the layout of the files.[134]

HDD data transfer rate depends upon the rotational speed of the platters and the data recording density. Because heat and vibration limit rotational speed, advancing density becomes the main method to improve sequential transfer rates. Higher speeds require a more powerful spindle motor, which creates more heat. While areal density advances by increasing both the number of tracks across the disk and the number of sectors per track,[137] only the latter increases the data transfer rate for a given rpm. Since data transfer rate performance tracks only one of the two components of areal density, its performance improves at a lower rate.[138]

[edit]

Other performance considerations include quality-adjusted price, power consumption, audible noise, and both operating and non-operating shock resistance.

Access and interfaces[edit]

Main article: Hard disk drive interface

2.5-inch SATA drive on top of 3.5-inch SATA drive, showing close-up of (7-pin) data and (15-pin) power connectors

Current hard drives connect to a computer over one of several bus types, including parallel ATA, Serial ATA, SCSI, Serial Attached SCSI (SAS), and Fibre Channel. Some drives, especially external portable drives, use IEEE 1394, or USB. All of these interfaces are digital; electronics on the drive process the analog signals from the read/write heads. Current drives present a consistent interface to the rest of the computer, independent of the data encoding scheme used internally, and independent of the physical number of disks and heads within the drive.

Typically a DSP in the electronics inside the drive takes the raw analog voltages from the read head and uses PRML and Reed–Solomon error correction[139] to decode the data, then sends that data out the standard interface. That DSP also watches the error rate detected by error detection and correction, and performs bad sector remapping, data collection for Self-Monitoring, Analysis, and Reporting Technology, and other internal tasks.

Modern interfaces connect the drive to the host interface with a single data/control cable. Each drive also has an additional power cable, usually direct to the power supply unit. Older interfaces had separate cables for data signals and for drive control signals.

  • Small Computer System Interface (SCSI), originally named SASI for Shugart Associates System Interface, was standard on servers, workstations, Commodore Amiga, Atari ST and Apple Macintosh computers through the mid-1990s, by which time most models had been transitioned to newer interfaces. The length limit of the data cable allows for external SCSI devices. The SCSI command set is still used in the more modern SAS interface.
  • Integrated Drive Electronics (IDE), later standardized under the name AT Attachment (ATA, with the alias PATA (Parallel ATA) retroactively added upon introduction of SATA) moved the HDD controller from the interface card to the disk drive. This helped to standardize the host/controller interface, reduce the programming complexity in the host device driver, and reduced system cost and complexity. The 40-pin IDE/ATA connection transfers 16 bits of data at a time on the data cable. The data cable was originally 40-conductor, but later higher speed requirements led to an "ultra DMA" (UDMA) mode using an 80-conductor cable with additional wires to reduce crosstalk at high speed.
  • EIDE was an unofficial update (by Western Digital) to the original IDE standard, with the key improvement being the use of direct memory access (DMA) to transfer data between the disk and the computer without the involvement of the CPU, an improvement later adopted by the official ATA standards. By directly transferring data between memory and disk, DMA eliminates the need for the CPU to copy byte per byte, therefore allowing it to process other tasks while the data transfer occurs.
  • Fibre Channel (FC) is a successor to parallel SCSI interface on enterprise market. It is a serial protocol. In disk drives usually the Fibre Channel Arbitrated Loop (FC-AL) connection topology is used. FC has much broader usage than mere disk interfaces, and it is the cornerstone of storage area networks (SANs). Recently other protocols for this field, like iSCSI and ATA over Ethernet have been developed as well. Confusingly, drives usually use copper twisted-pair cables for Fibre Channel, not fibre optics. The latter are traditionally reserved for larger devices, such as servers or disk array controllers.
  • Serial Attached SCSI (SAS). The SAS is a new generation serial communication protocol for devices designed to allow for much higher speed data transfers and is compatible with SATA. SAS uses a mechanically compatible data and power connector to standard 3.5-inch SATA1/SATA2 HDDs, and many server-oriented SAS RAID controllers are also capable of addressing SATA HDDs. SAS uses serial communication instead of the parallel method found in traditional SCSI devices but still uses SCSI commands.
  • Serial ATA (SATA). The SATA data cable has one data pair for differential transmission of data to the device, and one pair for differential receiving from the device, just like EIA-422. That requires that data be transmitted serially. A similar differential signaling system is used in RS485, LocalTalk, USB, FireWire, and differential SCSI. SATA I to III are designed to be compatible with, and use, a subset of SAS commands, and compatible interfaces. Therefore, a SATA hard drive can be connected to and controlled by a SAS hard drive controller (with some minor exceptions such as drives/controllers with limited compatibility). However they cannot be connected the other way round—a SATA controller cannot be connected to a SAS drive.

Integrity and failure[edit]

Close-up of an HDD head resting on a disk platter; its mirror reflection is visible on the platter surface. Unless the head is on a landing zone, the heads touching the platters while in operation can be catastrophic.

Main articles: Hard disk drive failure, Head crash, and Data recovery

See also: Solid-state drive § SSD reliability and failure modes

Due to the extremely close spacing between the heads and the disk surface, HDDs are vulnerable to being damaged by a head crash – a failure of the disk in which the head scrapes across the platter surface, often grinding away the thin magnetic film and causing data loss. Head crashes can be caused by electronic failure, a sudden power failure, physical shock, contamination of the drive's internal enclosure, wear and tear, corrosion, or poorly manufactured platters and heads.

The HDD's spindle system relies on air density inside the disk enclosure to support the heads at their proper flying height while the disk rotates. HDDs require a certain range of air densities to operate properly. The connection to the external environment and density occurs through a small hole in the enclosure (about 0.5 mm in breadth), usually with a filter on the inside (the breather filter).[140] If the air density is too low, then there is not enough lift for the flying head, so the head gets too close to the disk, and there is a risk of head crashes and data loss. Specially manufactured sealed and pressurized disks are needed for reliable high-altitude operation, above about 3,000 m (9,800 ft).[141] Modern disks include temperature sensors and adjust their operation to the operating environment. Breather holes can be seen on all disk drives – they usually have a sticker next to them, warning the user not to cover the holes. The air inside the operating drive is constantly moving too, being swept in motion by friction with the spinning platters. This air passes through an internal recirculation (or "recirc") filter to remove any leftover contaminants from manufacture, any particles or chemicals that may have somehow entered the enclosure, and any particles or outgassing generated internally in normal operation. Very high humidity present for extended periods of time can corrode the heads and platters. An exception to this are hermetically sealed, helium filled HDDs that largely eliminate environmental issues that can arise due to humidity or atmospheric pressure changes. Such HDDs were introduced by HGST in their first successful high volume implementation in 2013.

For giant magnetoresistive (GMR) heads in particular, a minor head crash from contamination (that does not remove the magnetic surface of the disk) still results in the head temporarily overheating, due to friction with the disk surface, and can render the data unreadable for a short period until the head temperature stabilizes (so called "thermal asperity", a problem which can partially be dealt with by proper electronic filtering of the read signal).

When the logic board of a hard disk fails, the drive can often be restored to functioning order and the data recovered by replacing the circuit board with one of an identical hard disk. In the case of read-write head faults, they can be replaced using specialized tools in a dust-free environment. If the disk platters are undamaged, they can be transferred into an identical enclosure and the data can be copied or cloned onto a new drive. In the event of disk-platter failures, disassembly and imaging of the disk platters may be required.[142] For logical damage to file systems, a variety of tools, including fsck on UNIX-like systems and CHKDSK on Windows, can be used for data recovery. Recovery from logical damage can require file carving.

A common expectation is that hard disk drives designed and marketed for server use will fail less frequently than consumer-grade drives usually used in desktop computers. However, two independent studies by Carnegie Mellon University[143] and Google[144] found that the "grade" of a drive does not relate to the drive's failure rate.

A 2011 summary of research, into SSD and magnetic disk failure patterns by Tom's Hardware summarized research findings as follows:[145]

  • Mean time between failures (MTBF) does not indicate reliability; the annualized failure rate is higher and usually more relevant.
  • HDDs do not tend to fail during early use, and temperature has only a minor effect; instead, failure rates steadily increase with age.
  • S.M.A.R.T. warns of mechanical issues but not other issues affecting reliability, and is therefore not a reliable indicator of condition.[146]
  • Failure rates of drives sold as "enterprise" and "consumer" are "very much similar", although these drive types are customized for their different operating environments.[147][148]
  • In drive arrays, one drive's failure significantly increases the short-term risk of a second drive failing.

As of 2019[update], Backblaze, a storage provider reported an annualized failure rate of two percent per year for a storage farm with 110,000 off-the-shelf HDDs with the reliability varying widely between models and manufacturers.[149] Backblaze subsequently reported that the failure rate for HDDs and SSD of equivalent age was similar.[8]

To minimize cost and overcome failures of individual HDDs, storage systems providers rely on redundant HDD arrays. HDDs that fail are replaced on an ongoing basis.[149][96]

Market segments[edit]

Consumer segment[edit]

Two high-end consumer SATA 2.5-inch 10,000 rpm HDDs, factory-mounted in 3.5-inch adapter frames
Desktop HDDs
Desktop HDDs typically have two to five internal platters, rotate at 5,400 to 10,000 rpm, and have a media transfer rate of 0.5 Gbit/s or higher (1 GB = 109 bytes; 1 Gbit/s = 109 bit/s). Earlier (1980-1990s) drives tend to be slower in rotation speed. As of May 2019[update], the highest-capacity desktop HDDs stored 16 TB,[150][151] with plans to release 18 TB drives later in 2019.[152] 18 TB HDDs were released in 2020. As of 2016[update], the typical speed of a hard drive in an average desktop computer is 7,200 RPM, whereas low-cost desktop computers may use 5,900 RPM or 5,400 RPM drives. For some time in the 2000s and early 2010s some desktop users and data centers also used 10,000 RPM drives such as Western Digital Raptor but such drives have become much rarer as of 2016[update] and are not commonly used now, having been replaced by NAND flash-based SSDs.
Mobile (laptop) HDDs
Smaller than their desktop and enterprise counterparts, they tend to be slower and have lower capacity, because typically has one internal platter and were 2.5" or 1.8" physical size instead of more common for desktops 3.5" form-factor. Mobile HDDs spin at 4,200 rpm, 5,200 rpm, 5,400 rpm, or 7,200 rpm, with 5,400 rpm being the most common. 7,200 rpm drives tend to be more expensive and have smaller capacities, while 4,200 rpm models usually have very high storage capacities. Because of smaller platter(s), mobile HDDs generally have lower capacity than their desktop counterparts.
Consumer electronics HDDs
They include drives embedded into digital video recorders and automotive vehicles. The former are configured to provide a guaranteed streaming capacity, even in the face of read and write errors, while the latter are built to resist larger amounts of shock. They usually spin at a speed of 5400 RPM.
External and portable HDDs
Two 2.5" external USB hard drives

See also: USB mass storage device class and Disk enclosure

Current external hard disk drives typically connect via USB-C; earlier models use an regular USB (sometimes with using of a pair of ports for better bandwidth) or (rarely), e.g., eSATA connection. Variants using USB 2.0 interface generally have slower data transfer rates when compared to internally mounted hard drives connected through SATA. Plug and play drive functionality offers system compatibility and features large storage options and portable design. As of March 2015[update], available capacities for external hard disk drives ranged from 500 GB to 10 TB.[153] External hard disk drives are usually available as assembled integrated products but may be also assembled by combining an external enclosure (with USB or other interface) with a separately purchased drive. They are available in 2.5-inch and 3.5-inch sizes; 2.5-inch variants are typically called portable external drives, while 3.5-inch variants are referred to as desktop external drives. "Portable" drives are packaged in smaller and lighter enclosures than the "desktop" drives; additionally, "portable" drives use power provided by the USB connection, while "desktop" drives require external power bricks. Features such as encryption, Wi-Fi connectivity,[154] biometric security or multiple interfaces (for example, FireWire) are available at a higher cost.[155] There are pre-assembled external hard disk drives that, when taken out from their enclosures, cannot be used internally in a laptop or desktop computer due to embedded USB interface on their printed circuit boards, and lack of SATA (or Parallel ATA) interfaces.[156][157]

Enterprise and business segment[edit]

Server and workstation HDDs
Typically used with multiple-user computers running enterprise software. Examples are: transaction processing databases, internet infrastructure (email, webserver, e-commerce), scientific computing software, and nearline storage management software. Enterprise drives commonly operate continuously ("24/7") in demanding environments while delivering the highest possible performance without sacrificing reliability. Maximum capacity is not the primary goal, and as a result the drives are often offered in capacities that are relatively low in relation to their cost.[158]
The fastest enterprise HDDs spin at 10,000 or 15,000 rpm, and can achieve sequential media transfer speeds above 1.6 Gbit/s[159] and a sustained transfer rate up to 1 Gbit/s.[159] Drives running at 10,000 or 15,000 rpm use smaller platters to mitigate increased power requirements (as they have less air drag) and therefore generally have lower capacity than the highest capacity desktop drives. Enterprise HDDs are commonly connected through Serial Attached SCSI (SAS) or Fibre Channel (FC). Some support multiple ports, so they can be connected to a redundant host bus adapter.
Enterprise HDDs can have sector sizes larger than 512 bytes (often 520, 524, 528 or 536 bytes). The additional per-sector space can be used by hardware RAID controllers or applications for storing Data Integrity Field (DIF) or Data Integrity Extensions (DIX) data, resulting in higher reliability and prevention of silent data corruption.[160]
Video recording HDDs
This line were similar to consumer video recording HDDs with stream stability requirements and similar to server HDDs with requirements to expandability support, but also they strongly oriented for growing of internal capacity. The main sacrifice for this segment is a writing and reading speed.[161]

Manufacturers and sales[edit]

Diagram of HDD manufacturer consolidation

See also: History of hard disk drives and List of defunct hard disk manufacturers

More than 200 companies have manufactured HDDs over time, but consolidations have concentrated production to just three manufacturers today: Western Digital, Seagate, and Toshiba. Production is mainly in the Pacific rim.

Worldwide revenue for disk storage declined eight percent per year, from a peak of $38 billion in 2012 to $22 billion (estimated) in 2019.[48] Production of HDD storage grew 15% per year during 2011–2017, from 335 to 780 exabytes per year.[162] HDD shipments declined seven percent per year during this time period, from 620 to 406 million units.[162][85] HDD shipments were projected to drop by 18% during 2018–2019, from 375 million to 309 million units.[163] In 2018, Seagate has 40% of unit shipments, Western Digital has 37% of unit shipments, while Toshiba has 23% of unit shipments.[164] The average sales price for the two largest manufacturers was $60 per unit in 2015.[165]

Competition from SSDs[edit]

HDDs are being superseded by solid-state drives (SSDs) in markets where their higher speed (up to 4950 megabytes) (4.95 gigabytes) per second for M.2 (NGFF) NVMe SSDs,[166] or 2500 megabytes (2.5 gigabytes) per second for PCIe expansion card drives[167]), ruggedness, and lower power are more important than price, since the bit cost of SSDs is four to nine times higher than HDDs.[17][16] As of 2016[update], HDDs are reported to have a failure rate of 2–9% per year, while SSDs have fewer failures: 1–3% per year.[168] However, SSDs have more un-correctable data errors than HDDs.[168]

SSDs offer larger capacities (up to 100 TB[46]) than the largest HDD and/or higher storage densities (100 TB and 30 TB SSDs are housed in 2.5 inch HDD cases but with the same height as a 3.5-inch HDD[169][170][171][172][173]), although their cost remains prohibitive.

A laboratory demonstration of a 1.33-Tb 3D NAND chip with 96 layers (NAND commonly used in solid state drives (SSDs)) had 5.5 Tbit/in2 as of 2019[update],[174] while the maximum areal density for HDDs is 1.5 Tbit/in2. The areal density of flash memory is doubling every two years, similar to Moore's law (40% per year) and faster than the 10–20% per year for HDDs. As of 2018[update], the maximum capacity was 16 terabytes for an HDD,[175] and 100 terabytes for an SSD.[31] HDDs were used in 70% of the desktop and notebook computers produced in 2016, and SSDs were used in 30%. The usage share of HDDs is declining and could drop below 50% in 2018–2019 according to one forecast, because SSDs are replacing smaller-capacity (less than one-terabyte) HDDs in desktop and notebook computers and MP3 players.[176]

The market for silicon-based flash memory (NAND) chips, used in SSDs and other applications, is growing faster than for HDDs. Worldwide NAND revenue grew 16% per year from $22 billion to $57 billion during 2011–2017, while production grew 45% per year from 19 exabytes to 175 exabytes.[162]

See also[edit]

Notes[edit]

  1. ^This is the original filing date of the application which led to US Patent 3,503,060, generally accepted as the definitive hard disk drive patent.[1]
  2. ^Further inequivalent terms used to describe various hard disk drives include disk drive, disk file, direct access storage device (DASD), CKD disk, and Winchester disk drive (after the IBM 3340). The term "DASD" includes other devices beside disks.
  3. ^Comparable in size to a large side-by-side refrigerator.
  4. ^ The 1.8-inch form factor is obsolete; sizes smaller than 2.5 inches have been replaced by flash memory.
  5. ^40 for user data, one for format tracks, 6 for alternate surfaces and one for maintenance.
  6. ^Initially gamma iron oxide particles in an epoxy binder, the recording layer in a modern HDD typically is domains of a granular Cobalt-Chrome-Platinum-based alloy physically isolated by an oxide to enable perpendicular recording.[54]
  7. ^Historically a variety of run-length limited codes have been used in magnetic recording including for example, codes named FM, MFM and GCR which are no longer used in modern HDDs.
  8. ^ abExpressed using decimal multiples.
  9. ^ abExpressed using binary multiples.

References[edit]

  1. ^Kean, David W., "IBM San Jose, A quarter century of innovation", 1977.
  2. ^Arpaci-Dusseau, Remzi H.; Arpaci-Dusseau, Andrea C. (2014). "Operating Systems: Three Easy Pieces, Chapter: Hard Disk Drives"(PDF). Arpaci-Dusseau Books. Archived(PDF) from the original on February 16, 2015. Retrieved March 7, 2014.
  3. ^Patterson, David; Hennessy, John (1971). Computer Organization and Design: The Hardware/Software Interface. Elsevier. p. 23. ISBN .
  4. ^Domingo, Joel. "SSD vs. HDD: What's the Difference?". PC Magazine UK. Archived from the original on March 28, 2018. Retrieved March 21, 2018.
  5. ^Mustafa, Naveed Ul; Armejach, Adria; Ozturk, Ozcan; Cristal, Adrian; Unsal, Osman S. (2016). "Implications of non-volatile memory as primary storage for database management systems". 2016 International Conference on Embedded Computer Systems: Architectures, Modeling and Simulation (SAMOS). IEEE. pp. 164–171. doi:10.1109/SAMOS.2016.7818344. hdl:11693/37609. ISBN . S2CID 17794134.
  6. ^ abcde"IBM Archives: IBM 350 disk storage unit". January 23, 2003. Archived from the original on May 31, 2008. Retrieved October 19, 2012.
  7. ^Shilov, Anton. "Demand for HDD Storage Booming: 240 EB Shipped in Q3 2019". www.anandtech.com.
  8. ^ abKlein, Andy (September 30, 2021). "Are SSDs Really More Reliable Than Hard Drives?". Backblaze. Retrieved September 30, 2021.
  9. ^"Validating the Reliability of Intel Solid-State Drives"(PDF). Intel. July 2011. Archived(PDF) from the original on October 19, 2016. Retrieved February 10, 2012.
  10. ^Fullerton, Eric (March 2018). "5th Non-Volatile Memories Workshop (NVMW 2018)"(PDF). IEEE. Archived from the original(PDF) on September 28, 2018. Retrieved April 23, 2018.
  11. ^Handy, James (July 31, 2012). "For the Lack of a Fab..." Objective Analysis. Archived from the original on January 1, 2013. Retrieved November 25, 2012.
  12. ^ abHutchinson, Lee. (June 25, 2012) How SSDs conquered mobile devices and modern OSesArchived July 7, 2017, at the Wayback Machine. Ars Technica. Retrieved January 7, 2013.
  13. ^ ab

Hi! I just got my new laptop XPS 15 and I've got some problems with my external hard drive (Freecom Tough drive 2TB, USB 3.0). It doesn't get recognized when I plug it.

It gets read only when I plug it (it does not get detected at this moment) and re-start the laptop (sometimes 2 or 3 times). So I do have to follow the same process every time because when I unplug it and plug it back in, it is not detected again.

And that trick only "works" with the left port. It does not get detected at all on the right port.

I am not sure where that problem comes from. It shouldn't come from a OS compatibility matter as the HD perfectly works on other laptop and computer, plus windows says I am up to date about the drivers. Maybe the USB drivers of the laptop are not up-to-date (but I run an analysis and that seems ok + I've got other HD USB3 and USB2 that works correctly). A power matter?

I can not change the wire of the hard drive I'm having issues with since it comes built-in.

Also, I managed to use that drive at the beginning when I was installing some software. After a moment I had a notification saying there was a problem with a USB device but I wasn't using it at that time so I didn't realize it was concerning my external HD. I found out later on that it was not and couldn't be detected anymore. It lasted something like 1 or 2h before the issue. To be noted all my other flash disks work well.

I ran a test with Driver Easy to check and had 25 things to update so I updated. At the end the sound didn't work anymore but I managed to find the right Dell drivers to have it back as before. My external HD is still no detected.

Does anyone faced the same situation and could share the solution?

I also feel like there is a connectivity matter too. The Wi-Fi seems to have some difficulties. Like loading internet pages takes a long time when I DL. Watching a YT video can also be difficult sometimes. This does not happen on the same network with other computers and laptops.

Thanks for your help!

A Disk Read Error Occurred on Windows 10 [Solved]

A disk read error occurred. Press Ctrl + Alt + Del to restart error pops up when you boot Windows 10. Even after you try to restart your computer, you get the same error message again. It’s very annoying, and the causes can vary from one to another, but the most common causes are:

  • Loose or faulty connections.
  • Insufficient RAM.
  • A damaged hard drive.
  • Incorrect MBR Configuration.

If you encounter A disk read error occurred on your Windows 10, don’t worry. Whatever the cause is, you can troubleshoot the issue and solve the problem with the following tried-and-true fixes.

Try these fixes:

No.1–Unplug any USB or DVD drive

No.2–Shut down your computer and cool it down for several hours

No.3-Reset or update your BIOS

No.4–Check your hard drives’ cables

No.5–Test RAM memory

No.6–Fix MBR and Fix Boot

Fix 1. Unplug any USB or DVD drive

If you have plugged in any removable flash drives like USB or DVD, usbhdd error 15, make sure to unplug them and then try to reboot your Windows 10. It’s possible that your system is trying to boot from one of the connected devices due to modification in boot priority.

After removing all these devices, check if the error still persists.

If you see the error again, there might be something wrong with your hard drive or configuration. You can move on to the next fix to solve usbhdd error 15 problem.


Fix 2. Shut down your computer and cool it down for several hours

Once A disk read error occurred pops upon your Windows 10, you need to shut down your computer and cool it down for a few hours like 5-8 hrs to usbhdd error 15 it a rest. After cooling down, turn on your computer to see if you can access Windows 10 normally.

It’s very likely that the temperature is causing the error. However, cooling down your computer takes for hours, usbhdd error 15, you can skip to the next fix if you’re in a rush.

If the your computer works properly, you need to back up usbhdd error 15 data and files to an external drive immediately before bumping into the same problem again.


Fix 3. Reset or update your BIOS

Resetting BIOS could fix A disk read error occurred error by restoring your system’s default settings. Here is how to do it:

1) Make sure you computer is turned off.

2) Turn on your computer and press F12 till BIOS screen pops up.

Note: The key to enter BIOS usually is F12, usbhdd error 15, but also could be F1, F10, Del, etc.
Just look carefully on the screen while your computer starts or check your user manual to know the exact key.

2) Use the down arrow key to choose Load Setup Defaults to reset your BIOS, then press Enter. Choose YES when you’re prompted to confirm the setup.

Note: For different computers, usbhdd error 15, the option to reset BIOS could also be Load Fail-Safe Defaults, Apply Default, Load BIOS Defaults, Load Default Settings, Load Setup Default, Factory settings, etc.

3) Use the down arrow key ↓ to choose Exit Saving Changes to exit BIOS.

4) Restart your computer to check if you can boot into your Windows 10 now.

Alternatively, you can also try to update your BIOS to fix disk read error. You should always have the latest BIOS version installed.


Fix 4. Check your hard drives cables

Check the cables connect your computer’s hard drives to your computer’s motherboard under its hood, usbhdd error 15. If the cable is loose or defective, disk errors may occur.

In this case, open your computer’s hood and check if each cable is fastened on both ends. Disconnect them, inspect the cables for any damage and then connect them firmly. Be sure to replace the faulty cables if you find any.


Fix 5. Test RAM memory

RAM(Random Access Memory) problem brings about various issues. As the RAM memory test is easy and non-destructive, you may as well do a complete test for RAM memory to fix the disk error.

  •  If you’ve added new RAM memory to computer recently, try to remove it and leave only one RAM. Then restart computer to check if the error still occurs.
  • Leave one RAM module on one slot and restart computer. If the disk read error still occurs, move the RAM to the other slot and start computer again.

Now you can see if you can boot into Windows again. If not, don’t give up here, you can try the next fix to solve the problem.


Fix 6, usbhdd error 15. Fix MBR and Fix Boot

This error might occur if there’s a problem with the Master Boot Record (MBR) file or the boot sector, usbhdd error 15. To fix them, you will need the original Windows 10 installation disc to repair the MBR and the boot sector. Here’s how to do it:

1) Boot from the original disk, then select the language.

2) Click Repair your computer, then select Command Prompt.

3) Enter the following Commands in the Command prompt separately and press Enter after each command:

bootrec /FixMbr bootrec /FixBoot bootrec /ScanOs bootrec /RebuildBcd

4) Now remove the disc from the drive.

5) Type exit and hit Enter.

exit

6) Now restart your computer and check if Windows is booting normally.

If unluckily, A disk read error occurred still exists after you tried all the fixes above, you can try to do a clean install of Windows 10. 


Bonus Tips:

If you run into computer problems randomly, there usbhdd error 15 be something wrong with your drivers. Missing or outdated drivers can cause many issues, usbhdd error 15. If you want to have better computer experience and prevent potential problems, it’s recommended to keep your drivers update to date.

To update your device drivers, you can visit the manufacture’s official website to find exactly the right the driver online, download it and install it step by step. You’ll need some computer skills and patience to update your drivers this way.

If you don’t have time or patience to manually update your network drivers, you can do it automatically with Driver Easy. It’s all done with just a couple of mouse clicks – easy even if you’re a computer newbie.

Driver Easy will automatically recognize your system and find the correct drivers for it. You don’t need to know exactly what system your computer is running, you don’t need to risk downloading and installing the usbhdd error 15 driver, and you don’t need to worry about making a mistake when installing.

You can update your drivers automatically with either the FREE or the Pro version of Driver Easy, usbhdd error 15. But with the Pro version it takes just 2 clicks (and you get full support and usbhdd error 15 30-day money back guarantee):

1) Download and install Driver Easy.

2) Run Driver Easy and click the Scan Now button. Driver Easy will then scan your computer and detect any problem drivers.

3) Click the Update button next to the flagged driver to automatically download the correct version of that driver, then you can manually install it (you can do this with the FREE version).

Or

Click Update All to automatically download and install the correct version of all the drivers that are missing or out of date on your system. (This requires the Pro version which comes with full support and a 30-day money back guarantee. You’ll be prompted to upgrade when you click Update All.)

4) Restart your computer for the changes to take effect.

Note: If you have any problems while using Driver Easy, feel free to contact our support team at [email protected].


Hopefully, one of these fixes can help you sole your disk read error. If you have any questions, feel free to add a comment below and let us know.

20

20 people found this helpful

Hi! I just got my new laptop XPS 15 and I've got some problems with my external hard drive (Freecom Tough drive 2TB, USB 3.0). It doesn't get recognized when I plug it.

It gets read only when I plug it (it does not get detected at this moment) and re-start the laptop (sometimes 2 or 3 times). So I do have to follow the same process every time because when I unplug it and plug it back in, usbhdd error 15, it is not detected again.

And that trick only "works" with the left port. It does not get detected at all on the right port.

I am not sure where that problem comes from. It shouldn't come from a OS compatibility matter as the HD perfectly works on other laptop and computer, plus windows says I am up to date about the drivers. Maybe the USB drivers of the laptop are not up-to-date (but I run an analysis and that seems ok + I've got other HD USB3 and USB2 that works correctly). A power matter?

I can not change the wire of the hard drive I'm having issues with since it comes built-in.

Also, I managed to use that drive at the beginning when I was installing some software. After a moment I had a notification saying there was a problem with a USB device but I wasn't using it at that time so I didn't realize it was concerning my external Usbhdd error 15. I found out later on that it was not and couldn't be detected anymore. It lasted something like 1 or 2h before the issue. To be noted all my other flash disks work well.

I ran a test with Driver Easy to check and had 25 things to update so I updated. At the end the sound didn't work anymore but I managed to find the right Dell drivers to have it back as before. My external HD is still no detected.

Does anyone faced the usbhdd error 15 situation and could share the solution?

I also feel like there is a connectivity matter too. The Wi-Fi seems to have some difficulties. Like loading internet usbhdd error 15 takes a long time when I DL. Watching a YT video can also be difficult sometimes. This does not happen on the same network with other computers and laptops.

Thanks for your help!

SMART Error for HDD, cannot mount drive

In Ubuntu (Linux) you couldn't mount the drive, but it sounds like you gave up too easily, usbhdd error 15, there's a world of difference between "filesystem inconsistencies / wasn't cleanly unmounted" that httpd syntax error on line 74 let an automatic mount, and "not recognized as a device, can't read a single sector" that you can read data & work with. Mounting can fail if windows is in "fast shutdown" mode, or there's filesystem errors, so it's definitely not a show stopper that it couldn't mount.

If a new appears then you can read (or at least attempt to read) the drive, and read SMART info & attempt tests. Since it's a USB drive, after connecting it a new device (X could be any letter) should show up, see & /var/log/syslog for info (especially errors if there's no new device - without a device it might not be possible to read anything, or even harder to try).

If you can read anything from the device then it's looking much better that (in package named gddrescue) or / or something can get some data. Probably need root rights too, withusbhdd error 15. Like or .

  • A very basic "read a little" with would be:

    reading the first M (=1024*1024 bytes) from the drive, and

    • is how many bytes to read/write in each "block"
    • is the number of "blocks" to take
    • skip N ibs-sized blocks at start of input
    • Just don't mix up theit will overwrite almost anything!
  • To skip 1000M's and then read 1M, use:

See https://wiki.archlinux.org/index.php/file_recovery and/or https://help.ubuntu.com/community/DataRecovery for more info, it can be involved. gddrescue has a great (but dry) GNU ddrescue Manual too, and search the web for lots more info.

& are the easiest to use IMO, I don't even bother with foremost or scalpel. Their homepages have good guides, see TestDisk's & TestDisk Step By Step and PhotoRec's & PhotoRec Step By Step. If testdisk can read the existing files, then copying them might be fairly easy, photorec doesn't save original filenames or directory structure.

Sometimes errors will show up when attempting reads & they might fail, error messages will probably flood & /var/log/syslog then, I like to keep a terminal open running &/or to see new errors as they arrive. If you've got the space on another device, usbhdd error 15, making a whole copy with gddrescue might be a good idea, it tries to skip over error sectors and read all the "good stuff" first, then try errors again later (or read "backwards", usbhdd error 15, jump around, etc).


You could use (in the smartmontools package) to read the SMART data & find out what it's errors are, even run new tests (but if the drive is failing, more tests could run down the clock on it's remaining life, so a backup first might be prudent). Here's my "notes" on :

Commands to generate reports:

  • - prints all SMART info
  • - prints all SMART and non-SMART info

If you're tracking changes, you could run a test every so often, saving it to a date-named file with:

To just get the "stats":

sudo smartctl -A /dev/sdX > $(date +"%Y-%m-%d_%H.%M")-sdX-smart-A

Tests

Use the option usbhdd error 15 TYPE is one of:

short maybe ~2min
conveyance maybe ~5m
long maybe ~55m
offline maybe ~73m (4380s)
[times are examples from an old drive]

But not all drives support all tests.

The option has a "Self-test execution status:" line that tells the current test's % remaining (if a test is running).

To see status could use:

USB Raid HDD Disconnecting and not remounting

  • I'm having an issue where my drive disconnects after a bit of use or during heavy use.

    It is a LaCie 2big with 2 14TB WD drives set into raid 1.

    It connects over USB 3 and has its own 12v power supply.

    Most of these end up being a power supply issue but the thing is this drive worked fine on windows and only has this issue when connected to my OMV setup.

    The drive disconnects and then comes back as a new drive.

    before:

    A8apmq9.png

    after:

    1dDkedG.png

    From what I read the dmesg logs can offer some insight into this, so I ran and then forced its hand at a disconnect:

    Display More

    Let me know if you guys have any ideas for this or further debugging steps I can try, produces much of the same:

    Display More

    Images

  • Would using fstab like in this article help?

    https://blog.backslasher.net/a…surviving-reconnects.html

    Some of the other posts on the subject mentioned their drives getting a new serial number when it disconnects but mine luckily stays the same. Is fstab the way to go to get it to remount or would that mess up something in OMV?

    EDIT: mount -a makes the drive return to the shares but then photoprism has to be restarted. usbhdd error 15 there a way to automate mount-a and allow photoprism to reconnect without having to podman restart it?

  • Yes but I still have to run that every 5 minutes or however long it takes to disconnect manually. That takes it from two commands to one that I enter but usbhdd error 15 still done manually.

  • Yes but I still have to run that every 5 minutes or however long it takes to disconnect manually. That takes it from two commands to one that I enter but its still done manually.

    Make a scheduled job to run it every x minutes on the GUI and you don't need to care about it anymore.

    It's a patch but as long as it works.

  • Make a scheduled job to run it every x minutes on the Dwl 2100 tx error and you don't need to care about it anymore.

    It's a patch but as long as it works.

    That would be an alright workaround but its still waiting 5+ minutes for the mount and photorism reboot., usbhdd error 15. Are there any ways to debug what might cause the USB to be disconnecting in the first place or not require restarting photoprism and still allow it to access the new mount/remount?

  • Are there any ways to debug what might cause the USB to be disconnecting in the first place

    That is something that you need to ask LaCie.

    Those boxes are made for Windows and the controller they have probably doesn't work well on Linux.

    A firmware update from with a fix would be the right solution.

    Only experience I had with the same issue was with a wd passpoRT 4tb portable:

    If Usbhdd error 15 left the drive connected all the time, usbhdd error 15, after a while idling, I wouldn't see it anymore (even on Windows).

    Only way to wake it up was rebooting.

    Sorry, not the best solution

External USB Hard Drive i/o error

I have an external USB hard drive that seems to have crashed. When I plug it into any of my computers it usually will not mount. Occasionally, usbhdd error 15, it does mount, but then when I run an command for instance nothing ever comes back, usbhdd error 15. The drive is split into four distinct partitions, usbhdd error 15, the biggest one, and the one that I would like to recover is a data partition of about 953 GB.

When I run (on my Ubuntu Linux system) I get these errors, the clearest of which seems to be reporting an I/O error:

Does anyone know how I might go about diagnosing the problem here, and if at all possible recovering the data on this hard drive?

Update:

I decided to follow these instructions about recovering a bad superblock from a corrupted drive. Error resolving stream host [waiting 30s] involved running the command. When I did that, I go the following error. I'm not sure how to answer that:

When I answered yes, I just got another for the next block (164868). Is this a bad sign? Is there a next step I should take from here perhaps?

Update 2:

It looks to me as though the disk is really far gone. I ran ddrescue and here were the results:

Is this a lost cause?

0 Comments

Leave a Comment