The tech industry has been buzzing about solid state drives (SSDs) again lately, but many questions remain. Even after many major vendors (Apple, EMC, and Dell to name a few) have introduced NAND flash-based disk into their core products, it is unclear whether non-disk storage will fly or flop. I’m betting it will find a nice niche, but that traditional spinning disks are here for a good long time.

Apple’s Flashing Success

When Apple switched from hard disks to flash in their mainstream product line, the world was abuzz with the novelty: Would flash displace hard drives? Sure, the company still offered disk-based storage for those needing vast capacity, but most people found that 8 GB or so of storage was plenty for daily use. Of course, instead of the MacBook Air, I’m talking about the iPod family, which contains just a single disk-based model.

Like the Air, the iPod demonstrates that what matters in the “take it with you” market is portability in the form of low weight, perceived durability, and compact dimensions. And NAND flash excels when it comes to packaging. The flash-based iPod is an excellent semaphore for this market segment in other ways, too. Audio files are fairly small, so music users don’t need all that much storage, relatively speaking. They will gladly ignore the cost per GB, too, at such small capacity points: iPod Nano buyers pay ten times more per GB than iPod Classic buyers.

In the case of the iPod, the compact size and joggable durability afforded by the flash iPods is worth the money to most buyers, not that flash player has sufficient capacity to meet their needs. The MacBook Air teaches a slightly different lesson: Although reviewers are quick to point out that the speed and battery life difference between the hard disk and NAND flash versions of the mini notebook are negligible, early buyers were happy to pay $1000 extra to skip the disk. In this case, they paid for quick access time, light weight, and durability that exist as much in their perception as in real-world benchmarks.

EMC’s Heavyweight Champion

In the exact opposite corner of the data storage world lurks EMC’s top-line Symmetrix DMX storage array. When the company announced the availability of NAND flash drives as their top-tier choice for storage, it turned the heads of the whole enterprise storage industry. Although the technology implementation is substantially different from Apple’s iPod, EMC’s move suggests that another group of customers exists who are similarly unimpressed by a low cost per GB: Enterprise application managers.

Many have suggested that enterprise flash is not yet competitive in terms of price, capacity, reliability, or even performance. And they have publicly disagreed with EMC CEO, Joe Tucci, who claimed effective parity after 2010 at last year’s EMC World event. After all, today’s enterprise flash drives are far more than ten times more expensive than their spinning brothers, and disk capacity continues to march higher by the month.

But the comparison is not about the cost of apples or oranges. In the enterprise storage space, flash drives sot at the top of the pyramid, with just a few units added into the traditional tiered storage mix as a “tier zero” of maximum performance. It is not as simple as pulling out a set of 146 GB FC drives and replacing them with a similar number of flash units. Instead, a few key applications or data sets are migrated up to the pinnacle, with the rest of the stack remaining the same.

There is huge promise when this tiered model is combined with storage virtualization, especially the automated variety. If the tiny percentage of storage that truly needs top-tier performance could be moved to a few solid state disks, the whole stack will benefit from reduced device contention. If automation could make the decision on a block-by-block basis, the effectiveness would be much greater.

I Still Remember

There is another kind of solid state disk in play, too. For over two decades, company after company has pushed the idea of packaging high-performance DRAM as a disk substitute for enterprise storage, just as EMC has now done with NAND. These RAM-based disks offer even higher performance and prices than their flash-based cousins, and none has taken the industry by storm.

Way back when a tiny EMC was one purveyor of solid state storage, I recall the philosophical conundrum posed by the devices: Is it better to package DRAM as storage and use it in a conventional manner or to use that same memory as a cache for actual disks? The market voted for the latter, with EMC and others introducing in-array cache to accelerate RAID to great effect. System memory expanded in parallel, with modern servers optimally caching data in three or more levels internally as well.

Where Does the Flash Go?

For most uses, this is precisely the correct configuration. The priciest and quickest “storage” is placed close to the CPU, with performance and cost dropping and capacity increasing as one moves outward.

Where does flash belong, then? Apple teaches us that NAND flash delivers the goods when it comes to the portable market, and it is likely that the use of this technology in this area will only continue to grow. And EMC shows that there is a need for higher performance in the enterprise storage world as well, though perhaps not enough for pure DRAM devices.

The message is clear: As long as the cost of disk continues to lead, NAND flash will remain a niche product. There are certainly markets for NAND-based devices, from portable computing to the enterprise, but disk just works too well to be displaced. While one can never see too far into the future of storage, it seems clear that conventional hard disks will remain the dominant media for a few more generations of technology at least.

© sfoskett for Stephen Foskett, Pack Rat, 2008. | Flash Forward or Flash Back?
This post was categorized as Apple, Computer History, Enterprise storage. Each of my categories has its own feed if you'd like to filter out or focus on posts like this.

Homes now need data storage as well as closets...

This is part of an ongoing series of longer articles I will be posting every Sunday as part of an experiment in offering more in-depth content.

Along with my professional focus on enterprise storage systems, I’m enamored of home networking, and recently passed the three terabyte mark at home! This got me thinking about where home storage is heading.

As you can see in the photo, my office closet is overflowing with computer equipment (and one sweet guitar), but my data storage is much better organized. I have a hacked Linksys NSLU2 with 500 GB as a file server, a 500 GB PC backup disk, a 160 GB Time Machine disk, 1 TB of TiVo storage, and the rest. But wouldn’t it be nice if this could all be combined into some kind of super home server?

Past Failures: Home Servers

Home storage appliances and servers have come and gone over the year, with none seeming to make much of a mark. The market remains littered with UPNP media servers and home NAS boxes dashed on the shoals of an unappreciative public. Nearly every home network device company has produced one or two home storage servers, none of which have succeeded. Although I use a Linksys NSLU2 at home, I had to hack its Linux software and completely replace Linksys’ features to create a useful device! The un-hacked NAS devices of Buffalo, Western Digital, Netgear, and the rest have generally failed to find buyers as well. So far, consumers seem content with simple USB and FireWire external drives.

The most adventurous home storage servers came from Zetera and Ximeta, both of whom relied on proprietary IP SAN protocols. Note that these were SAN products, sharing block storage over Ethernet, rather than conventional NAS solutions. Both required drivers, limiting client support. The one Zetera buyer I know was pleased by the performance but never used the device as anything but a large hard drive for one PC.

Then there is Microsoft. Recall that the latest Windows Home Server is only their latest attempt to enter this market, and yet I know of no one who has adopted the device. The same can be said of the various media center servers from Microsoft and others. At this point, it seems likely that the future of home storage servers will not come from Microsoft, though their two XBox generations have great potential as clients.

Even EMC has entered the market with their nifty (but largely unnoticed) LifeLine product and Iomega acquisition. Supporting file services and backup for computers as well as audio and video for media players, EMC positions LifeLine much like their Retrospect backup product, but goes further in offering a complete software solution for hardware OEMs wanting to offer a non-Windows home server. Although an impressive offering, it is too early to tell if EMC will have much success with this product.

The Sleek, Shiny Elephant in the Living Room

Of course, there is one company that sells media players and servers by the bushel, complete with sleek, shiny interfaces. Apple’s tremendous success with the iPod has led to their iTunes software becoming the dominant media organization platform, complete with its own proprietary discovery and sharing protocol. Now, with the Apple TV and video iPods, the company is broadening into more media categories. Surely their dominance here puts them in a special position when it comes to setting the stage for a home server or storage revolution.

They also have a strong position in the world of dedicated home storage. Their Airport products are among the only routers to be widely implemented with shared storage. Although many other companies offer similar products, low customer understanding means that these functions are not widely used. And the new Time Capsule device is surely already the most widely-used home NAS product.

But Apple has not yet shown any home server strategy. Administering multiple iTunes servers can be frustrating for users, with no inter-iTunes synchronization or centralization capability. Although the Mac Mini, Apple TV, or Time Capsule could certainly be seen as a home server, the company does not position them as such in the market. Indeed, some iTunes users like myself rely on compatible third party media servers like Firefly and TwonkyVision rather than using iTunes itself. Still, rumors of an Apple home server persist.

One issue for Apple is their reliance on proprietary protocols. Although the Bonjour discovery protocol is certainly simpler than UPnP in practice, Apple stands alone in relying on it. They also steadfastly stick to AFP for NAS and DAAP for remote media streaming. This limits the number of third-party clients and servers that can be used with their hardware and software.

The Future is Friendly

Although Apple has not yet tipped a home storage strategy beyond Time Capsule and Airport Extreme, they are best positioned to deliver a real home storage solution. A simple step would be to create an iTunes media server integrated with Time Capsule and add client/server media synchronization. The company already has OS X backup and file services integrated, and this move would further centralize the digital home around Apple products. But the company’s reliance on closed protocols like DAAP is worrisome, since it locks consumers into nearly all-Apple solutions.

Microsoft’s Media Center and Home Server combination, based around UPnP, shows great promise, with many compatible third-party clients and servers already available. But my own experience with the solution has not been at all positive (I still can’t get my Roku SoundBridge, Vista Ultimate laptop, and Media Center PC to see each other!), leading me to question the viability of this option.

Although Apple or Microsoft could come to dominate, I suspect the future of home storage is out of both companies hands. A number of others are working on improved home server experiences, including EMC’s LifeLine and the expanding use of Debian Linux and open source tools. But all could be sidelined by improved Internet-based services. Google, Microsoft, and Apple continue to expand their online consumer suites with greater storage, synchronization, multimedia integration, and all have the potential to reduce or eliminate the need for in-home storage.

Although I cannot yet tell which service will win, one thing is certain: Consumers demand friendly, flexible solutions. They don’t want to fuss with their media, and they don’t want simple shared storage. They want integration with multiple devices and flexibility to access their content on any device. The first company to offer a simple, flexible storage server for the home will surely be on the right track!

© sfoskett for Stephen Foskett, Pack Rat, 2008. | The Future of Home Storage
This post was categorized as Apple, Computer History, Terabyte home. Each of my categories has its own feed if you'd like to filter out or focus on posts like this.

I am not the typical enterprise storage user. In fact, I am not an enterprise storage user at all – I am a consultant focused for over a decade on assisting enterprises with their storage architecture and strategy, working with businesses of all sizes. My background is both a blessing and a curse – I have seen far more enterprise storage environments in much more detail than most people, but I am unable to truly empathize with my corporate storage compatriots since it’s not really my gear and data that I am working with.

Based on this experience, what does the future hold? Where is enterprise storage heading? Read on for my thoughts.

Fibre Channel

Although the commoditizing storage market would seem ripe for stagnation, the opposite is happening. In fact, the enterprise storage market has continued to diversify, with iSCSI recently expanding the options for storage connectivity to a new market and FC seeing rapid uptake in the virtual server arena. Fibre Channel over Ethernet (FCoE), whether or not part of the datacenter Ethernet push, is joining virtualized I/O technology based on InfiniBand as the next wave in connectivity. Simply put, the market is not standing still.

Focus on the new world of storage area network (SAN) connectivity can take away from the basics, however. Traditional switched Fibre Channel (FC) remains the healthy market leader, and the recent upgrade to 8 Gb speed has attracted customer attention. Although they are unlikely to run out and perform a mass upgrade, 8 Gb FC is as as much of an inevitability as 4 and 2 Gb before it. The switch will be made, and customers will upgrade organically.

One of the big beneficiaries of 8 Gb FC will be those with virtual servers. This new hardware is coming just as N_Port ID virtualization (NPIV) is maturing, and this technology, which enables multiple servers to share a single FC interface, in combination with a doubling of bandwidth will make modern Fibre Channel tech extremely attractive to virtual server shops.

Even those who do not adopt 8 Gb FC connectivity in their SAN will benefit from the upshift in throughput, as native 8 Gb disks appear and enterprise arrays are redesigned to accept them, just as devices like the DMX-4 from EMC benefited from 4 Gb FC back ends.

IP Storage: iSCSI and NAS

As far as iSCSI goes, those of us who saw the promise of this technology can finally declare victory. Every storage device that matters offers iSCSI as a connectivity option, and most buyers are considering adopting it. It is being weighed fairly against FC, and the promise of reduced heterogeneity and cost are proving attractive to many. In fact, it is wrong to continually compare it against FC, since many iSCSI buyers would never adopt an FC SAN due to concerns about cost or learning curve. Indeed, much of the uptake in iSCSI comes from areas where SAN was never adopted, and iSCSI’s growth can be partly attributed to these happy customers spreading the technology wider than originally intended.

A hidden benefit of iSCSI adoption is the technologies and techniques that have come along with it. Clustering of smaller storage systems has become a common option for scalability, and has proven itself against old modular “head/shelf” arrays. Although the rate of adoption for security technologies like CHAP and IPsec in iSCSI remains low, they are far more common than their FC relatives. And Microsoft’s simplified and universal iSCSI drivers, which include multi-path and snapshot technologies, have been much more successful than their proprietary equivalents.

Let us not forget humble old network attached storage (NAS), either. File server consolidation to NAS filers continues to be a healthy (but less flashy) market, and NAS virtualization is on the rise as these devices proliferate. And some in the server virtualization community are beginning to consider NFS for their servers, especially when it comes to VMware. NAS definitely still has life and legs and will benefit from the shift to 10 Gb Ethernet just like iSCSI and FCoE.

The Future

As for the future, it is clear that most storage vendors are lining up behind Fibre Channel over Ethernet (FCoE) . Although true I/O virtualization, as envisioned by datacenter Ethernet (DCE) and InfiniBand, may not gain traction outside the largest data centers, FCoE seems to be the inevitable next generation for massive enterprise storage. Just about every vendor is committed to it, and the customers I have spoken to accept it as the future. Although 8 Gb FC might delay FCoE in some cases, it will almost certainly be the predominant SAN connectivity mechanism for large block storage devices within five years.

© sfoskett for Stephen Foskett, Pack Rat, 2008. | A Consultant’s View Of The Enterprise Storage Market
This post was categorized as Computer History, Enterprise storage, Virtual Storage. Each of my categories has its own feed if you'd like to filter out or focus on posts like this.