Category: Hard disk storage

WD cracks the 14 Terabyte barrier for a standard desktop hard disk

Article HGST UltraStar HS14 14Tb hard disk press image courtesy of Western Digital

Western Digital 14TB hard drive sets storage record | CNet

From the horse’s mouth

HGST by Western Digital

Ultrastar HS14 14Tb hard disk

Product Page

Press Release

My Comments

Western Digital had broken the record for data stored on a 3.5” hard disk by offering the HGST by WD UltraStar HS14 hard disk.

This 3.5” hard disk is capable of storing 14Tb of data and has been seen as a significant increase in data-density for disk-based mechanical data storage. It implements HelioSeal construction technology which yields a hermetically-sealed enclosure filled with helium that leads to thinner disks which also permit reduced cost, cooling requirements and power consumption.

At the moment, this hard disk is being pitched at heavy-duty enterprise, cloud and data-center computing applications rather than regular desktop or small-NAS applications. In this use case, I see that these ultra-high-capacity hard disks earn their keep would be localised data-processing applications where non-volatile secondary storage is an important part of the equation.

Such situations would include content-distribution networks such as the Netflix application or edge / fog computing applications where data has to be processed and held locally. Here, such applications that are dependent on relatively-small devices that can be installed close to where the data is created or consumed like telephone exchanges, street cabinets, or telecommunications rooms.

I would expect that this level of data-density will impact other hard disks and devices based on these hard disks. For example, applying it to the 2.5” hard-disk form factor could see these hard disks approaching 8Tb or more yielding highly capacious compact storage devices. Or that this same storage capacity is made available for hard drives that suit regular desktop computers and NAS units.

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What are the multiple drive layouts available in your NAS

WD MyCloud EX2 dual-disk NAS

WD MyCloud EX2 2-disk NAS – has a 2-disk RAID setup

All network-attached-storage units that have two or more drive bays in them offer different ways to make use of the hard disks installed in these drive bays. These are primarily about creating one logical disk volume out of the many disk drives.

You may also find multiple-disk arrays being implemented in so-called “Direct Attached Storage” devices which connect to your computer as if they are a peripheral or are integrated in the computer. These are typically used for computer setups where read-write performance for secondary storage is considered important like video editing or for computers that work as servers.

WD MyCloud EX4, WD MyCloud EX2, WD Red 6Tb hard disk

WD MyCloud EX4 NAS – can be set up as a 4-disk RAID array

The most common setups are described as “RAID” or “Redundant Array Of Independent Disks”. These setups gang multiple hard disks (or solid-state drives) to improve data throughput, effective disk capacity or system fault-tolerance.

Multi-Drive Disk setups

RAID setups

It is important to remember that a RAID setup that is about fault tolerance doesn’t obviate the need to back up the contents of a NAS. This is something you can do with a USB hard disk connected to the NAS, another NAS on the same network or connected via the Internet or an online storage or backup service.

RAID 0

RAID 0 Data striping data layout

RAID 0 Data Striping across disks

Here, this creates one logical volume with the data spread across the disks, a method known as “striping”. Each block of data is sequentially stored across each physical disk rather than a disk being filled with data then another disk being subsequently filled with data.

This allows for increased capacity and read / write data throughput, but loses on fault tolerance because the disk array is no good and the data is lost if one of the drives fails.

Volume Capacity: Number of Disks x Size of smallest disk

RAID 1

RAID 1 disk mirroring data layout

RAID 1 – Disk Mirroring

This setup creates a logical volume with the data duplicated on each physical drive. a method known as “mirroring”.

The main advantage here is increased fault-tolerance because if a disk dies, you still have access to the the data on the other disk. There is also another advantage of increased read throughput because both physical disks can be read at the same time.

The only limitations here are the volume capacity which is the size of the smallest disk in the array along with the write speed because the disk controller has to write the same data to multiple disks. It is infact a preferred RAID array setup for a 2-bay NAS due to the fault-tolerance.

Volume Capacity= Size of smallest disk in the bunch

RAID 5

RAID 5 Data Striping with parity Data layout

RAID 5 Data Striping with a parity block

This setup works between data capacity and fault tolerance in a very interesting way. It is because the RAID 5 setup creates “parity” data. This is used in computing as a fault-tolerance measure because an algorithm can use this data along with the “known-to-be-good” data to reconstitute data lost in transmission.

Here, a RAID 5 array stripes data across the physical disk collection but inserts a block of parity data at regular intervals as part of this “striping” so as to create some form of fault-tolerance. Then the RAID 5 disk controller reconstitutes data from parity and available “known-to-be-good” data if things start to go wrong with a disk.

The advantages in these setups are the disk capacity, the read throughput and the fault tolerance but there is a performance reduction for those systems that do a lot of data writing.

Volume Capacity: (Number of disks – 1) x smallest disk size

RAID 6

RAID 6 Data striping and two-block parity data layout

RAID 6 Data striping with two-block parity

RAID 6 works in a similar manner to RAID 5 in that it stripes data across multiple physical disks and creates a parity block for fault-tolerance. But a RAID 6 array creates another parity block to increase the amount of fault tolerance in the setup.

Volume capacity: (Number of disks-2) x smallest disk size

RAID 10 (1+0)

RAID 10 data layout

RAID 10 A combination of data striping and disk mirroring

A setup that is used with 4-disk RAID arrays is the RAID 10 array also known as the RAID 1+0 array which is a combination of both the RAID 1 setup and the RAID 0 setup.

Here, there are two collections of disks with one collection keeping copies of the data held on the other collection. Each collection has its data “striped” across the disks for capacity and performance.

The core benefit with a RAID 10 setup is that there is increased write throughput which can come in handy with write-intensive setups like databases. This is in addition to the fault tolerance provided by mirroring along with the read performance provided by striping.

Volume Capacity: Combined size of two of the smallest disks

Non-RAID setups

JBOD data layout

JBOD – Disks as separate volumes

JBOD

This setup, known as “Just a Bunch Of Disks” is simply about each physical disk being treated by the NAS as a separate logical volume. It can be useful if you want to maintain separate data on each disk under a separate volume name.

Spanning

Disk Spanning data layout

Disk Spanning, sometimes known as JBOD by some manufacturers

The “spanning” setup simply is based on data filling up one disk then filling up another disk in that same volume.

Array Type Disks Capacity Performance Fault
Tolerance
RAID 0 Min: 2 Yes Yes
RAID 1 Min: 2 Yes
improved read
Yes
Copied disks
RAID 5 Min: 3 Yes Yes
improved read
Yes
Parity
RAID 6 Min: 4 Yes Yes
improved read
Yes
dual parity
RAID 10 Min: 4
Even number of disks
Yes
improved write
Yes
Copied disk arrays
JBOD Logical volume / disk Yes
Spanning Min: 2 Yes

Different options available

Automatic RAID setups

Netgear ReadyNAS

The NETGEAR ReadyNAS on the right can implement X-RAID automatic RAID setup

An increasing number of manufacturers use an “automatic RAID” setup like Synology’s Hybrid RAID or NETGEAR’s X-RAID. These are RAID setups that are optimised to mix different-sized hard disks so that these arrays work to maximise useable capacity, disk performance and fault-tolerance.

Manufacturers pitch these RAID setups for people new to NAS or disk-array management who are thinking about how much redundant storage is needed to balance capacity and fault tolerance. They also encourage the customers to “build out” a RAID array as and when they can afford the extra disks.

Hot-spare disks

Thecus N5810PRO Small Business NAS press photo courtesy of Thecus

Thecus N5810PRO small business NAS is able to implement a hot-spare disk for high RAID availability

Another feature offered mainly with small-business NAS units is the addition of a hot-spare disk. Such RAID arrays will have a separate hard disk that isn’t used unless one of the disks in that array fails.  These setups are preferred for environments where there is emphasis on a multi-disk array that is to be highly available at peak performance.

Hot-swap setups

An increasing number of prosumer and small-business NAS units come with a “hot-swap” functionality where you can swap out the hard disk while the NAS is in operation. This is more so for replacing faulty disks that are degrading a RAID array’s performance and is more relevant with RAID 1, RAID 5, RAID 10 and “automatic RAID” setups.

Upsizing a NAS’s RAID array

QNAP 2-disk NAS

QNAP 2-disk NAS – capable of setting up a highly-available high-performance RAID1 array

Upsizing a RAID array is something you could be tempted to do, especially as hard-disk prices gradually become cheaper and the time when one hard disk in a RAID array fails may be the time to upsize it.

But this can be difficult. Here, you would need to copy out all of the data to storage with the same volume capacity as your NAS’s current RAID array. Then you would have to simultaneously replace the disks in that array with units of the same but higher capacity before copying back the data. This may be easy to achieve with a 2-bay NAS.

Or you could migrate a 2-disk RAID 1 array in a 4-bay NAS to a RAID 5 array while adding a higher-capacity disk to that array. Here, you get increased capacity on the new disk due to the smaller disks being combined for real data use while space on the larger disk is allocated for parity data. Then you would need to swap out the small disks in that array with the larger disks as a way to gradually increase the volume’s useful size.

The automatic RAID setups make it easier to upsize your NAS as you can afford it and manage the right amount of redundant storage needed for your data.

The best RAID array setup for your needs and your NAS

The RAID array that you set your NAS up with depends on the number of drive bays the device has along with the number of disks you have. But these suggests are based on setups that are cost-effective yet yield high availability . They would also yield high read performance especially for multimedia applications. It is also a good idea to populate your multiple-bay NAS with drives of the same capacity when you are setting a new unit up.

A 2-bay NAS would be best set up as a RAID-1 array in order to implement the mirroring ability for high availability and increased read throughput which is necessary for video files streamed using DLNA.

A 4-bay NAS would be best set up as a RAID-5 array of at least three disks of the same size. There is the ability to make use of the capacity yet use the parity blocks to keep the data available should one of the disks keel over.

Conclusion

Once you understand how the various RAID and other multi-disk arrays work, you can choose the most cost-effective way to have your data stored for capacity, performance and high availability with your NAS.

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Formatting external hard drives to native file systems may allow them to work optimumly

Article

Using external drives to save space on your Mac? Format them first. | MacFixIt – CNET Reviews

My Comments

External hard disk

A typical external hard disk

This article highlighted the benefits of formatting external hard disks that are to be connected to an Apple Macintosh as HFS+ file-system disks. This advice hails well for formatting an external hard disk to an operating system’s native file-system such as NTFS for Windows or ext3 for Linux. This is because most of the external hard disks come preformatted to FAT32 more as an interchangeable file system that can be used on Windows, Macintosh and UNIX/Linux.

In the context of an external hard disk that you attach to a network-attached storage device for extra capacity, it may be worth looking through the instruction manual for your NAS or router to find the optimum file system. Some of the NAS units may work with ext3 or NTFS as the file system whereas most, including the routers with NAS functionality will stay with FAT32.

But this situation would apply to external hard disks that are primarily connected to the host computer all of the time rather than the “portable” hard disks that are likely to be moved between different computers and file systems. It wouldn’t hold well with thumb-drives and memory cards that you would expect to move between various computer devices including specific-purpose devices because most of these devices would only know the common FAT32 file-system.

This advice is best applied with an external hard disk that you have just purchased rather than one that contains all of your data because a format routine can wipe all of the data that exists on the hard disk.

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TDK does amazing things to my home network by increasing the hard-disk data density further

Article

TDK breaks the Hard Drive density limit, could go on to develop super-sized storage — Engadget

My Comments

TDK was once known in its earlier years for storage media, especially tapes and, subsequently floppy and optical discs. During that time, when any of us wanted high-quality audio or video recording, we chose this name as one of our preferred brands. Infact one idea they were known for in the 1970s was a cost-effective high-bias magnetic tape formula known as “Super Avilyn” which yielded as good an audio or video recording result as traditional chrome-based high-bias magnetic tape.

Now that we have moved to MP3 players, smartphones and hard-disk-based storage of audio and video content, this company had diversified in to cheaper audio equipment to the open market and reduced its presence in storage media for that market. Here, Hitachi and others have been improving on the data capacity of hard disks over the many years with TDK disappearing in to the background in this field.

But they have not left this storage-medium expertise of theirs behind in this hard-disk-based data-storage era. Here, they raised the data-density bar for hard disks further, thus allowing for 1.5 terabyte per square inch. The article raised possibilities of 15” laptops coming with single 2.5” hard disks greater than 1Tb or desktop computers being equipped with 3.5” hard disks greater than 2Tb. This would also appeal to the current trend for low-profile and “all-in-one” desktops having the same storage as what was acceptable for larger designs.

For the home or small-business network, I would see possibilities like NAS units being in the order of at least 10Tb. This is in conjunction with PVRs and similar home-entertainment equipment able to work with many hours of ultra-high-definition video material especially as the 4K and 8K ultra-high-definition video technologies which yield cinema-quality video come closer.

Personally, I would expect this technology to materialise in the form of hard disks within the next two years once TDK have got it proven in a form for manufacturers to use. It also happens to be coinciding with the South-East-Asian hard-disk factories coming back on stream after the Thailand floods, this making it feasible to see the return of “dime-a-dozen” hard-disk storage.

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Hitachi outs a pair of 4TB HDDs for your storing pleasure — Engadget

Article

Hitachi outs a pair of 4TB HDDs for your storing pleasure — Engadget

My Comments

Hitachi has raised the ante again for hard-disk storage by delivering a 4Tb 3.5” hard-disk unit. They have packaged it as a retail-sold aftermarket retrofit kit with SATA connectivity for around US$399 and as a USB 3.0-connected external hard disk for US$420.

The Engadget article went on about us thinking of cloud storage as the way to go for personal data storage and that it would please those of us who place emphasis on desktop-local or NAS-hosted data storage. This would include most business operators who want direct control over their business data. I also see this hard disk as being relevant to the network-attached storage sector where you place emphasis on data capacity with these devices as they become local warehouses for high-definition video, high-quality music and high-resolution photos.

A question that may need to be raised with NAS applications is whether the NAS’s firmware / operating-system can address unique physical disks with a capacity of 4 or more terabytes. Here, I would suspect that most Linux-based firmwares could do so but even if the current firmware can’t address the 4Tb or more physical disk, a subsequent version could support the volume size.

Of course, as more hard-disk plants in Taiwan get back to full steam after the floods and more of the 4Tb hard disks come on the market, the prices could reduce where this capacity becomes more reasonable for home and small-business users. Other interesting factors that could come of this include the development of single-unit 2.5” hard disks with capacities of 1Tb or greater or smaller hard-disks with higher capacities that would appeal to those of us with a need for higher mobile data capacity.

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SSD drives now available for IDE-based computers

News articles

Du SSD pour les “vieilles” bécanes | Le Journal du Geek (France – French language)

My comments

You may be keeping an older IDE-based computer going or have a computer which has one IDE bus but plenty of SATA connectors on the motherboard. Hey, you may think of adding a solid-state drive to this computer in order to benefit from high operating speeds and low energy consumption but the fact that the only vacant secondary-storage interface is IDE-based throws your plans haywire.

What Buffalo has now done is to provide an SSD which connects to the IDE bus on these computers. The main limitation with this is that they only come in a 2.5” chassis, which means that you may have to use a 2.5” mounting kit and adaptor plugs if the computer you plan to upgrade is your desktop rig. They have a 64Mb cache and come in capacities of 32Gb, 64Gb and 128Gb with a price list of USD$250, USD$360 and USD$630 respectively. This may be a steep premium to pay if you want that quicker boot time for your older computer.

In my opinion, I would place the 64Gb drive as a drop-in replacement for the system drive (operating system, program files) in a multi-drive computer while keeping the “data” drives as regular rotary drives. Here, this could lead to quick boots and application starts without much power being used. The 128Gb drive may be useful as a drop-in replacement for the hard drives in older laptops that have a fair bit of life in them so as to keep them running longer on their batteries.

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Buffalo ships world’s first USB 3.0 hard disk drives this month – Engadget

Buffalo ships world’s first USB 3.0 hard disk drives this month | Engadget

My comments on this article

What has pleased me about Buffalo releasing the world’s first USB 3.0 external hard disk is that they have taken a “systems” approach to getting the standard off the ground. This is through supplying a USB 3.0 PCI-Express interface card for use with recent-issue desktop computers with a vacant PCI-Express x1 slot on the motherboard as well as, of course, the necessary cables.

It may appeal to those of us who like to take apart and put together desktop computers a lot and are likely to build “homebrew” server systems. But wait for 6 months to a year and the USB 3.0 sockets will appear as part of the next generation of motherboards and be integral to laptop computers and other small-form-factor systems.

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QNAP Intros the First 2.5-inch SATA, 8-bay, Intel Atom-based NAS – QNAP Press Release

QNAP Intros the First 2.5-inch SATA, 8-bay, Intel Atom-based SS-839 Pro Turbo NAS. ( Press Release ) – Quality Network Appliance Provider

HEXUS.Net article, EHomeUpgrade article

My comments on this 2.5” hard-disk NAS

Initially, the use of a 2.5” hard disk in a NAS would have been simply considered as a “toy” but there are more “business-class” multi-disk NAS units like this one come on the scene that use these disks. This QNAP unit – the SS-839 Pro – impressed me because of the fact that there is a NAS fit for the business or “muscle-NAS” market that give respect to this low-power small form factor.

It also can hold 8 of the disks in the same footprint as a typical 5-bay “muscle NAS”, with support for sophisticated RAID and “business server” functionalities available in this class of device. Another benefit that I also like is the ability to have less power consumption than a NAS of this class and can provide for more expandability as one’s data needs grow.

Once the 1 Tb 2.5” hard disk comes on the scene, this will certainly wipe the 3.5” form factor off the map as far as hard disks are concerned and make that size only for certain removeable media.

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HEXUS.net – News :: Deal of the day: 1TB Hitachi Deskstar hard drive for under £52 : Page – 1/1

Is this a sign of the times with hard disks? Time to keep an eye on the swap meets and the Internet for this special so you can add extra capacity to the PC or NAS. You may even consider running 2 or more of them in a fail-safe RAID array to protect against loss of data

Cited article

HEXUS.net – News :: Deal of the day: 1TB Hitachi Deskstar hard drive for under £52 : Page – 1/1

Hard-disk storage continues to get cheaper by the day, but we’ve yet to see anything as cheap as this:

It’s the Hitachi DeskStar 1TB hard drive, and it’s being offered at bargain-basement prices on various websites. The cheapest we’ve seen, though, is Ebuyer.com who is currently offering the drive for just £51.82 delivered. That’s around 5p per gigabyte, for a 7,200rpm SATA drive with a 16MB cache. It just doesn’t get much cheaper than that, if at all.

Ebuyer’s website reckons the etailer has over 800 in stock, so this could be a good opportunity to max out your PC or NAS.

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