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Tony Pearson is a Master Inventor, Senior IT Architect and Event Content Manager for [IBM Systems for IBM Systems Technical University] events. With over 30 years with IBM Systems, Tony is frequent traveler, speaking to clients at events throughout the world.
Lloyd Dean is an IBM Senior Certified Executive IT Architect in Infrastructure Architecture. Lloyd has held numerous senior technical roles at IBM during his 19 plus years at IBM. Lloyd most recently has been leading efforts across the Communication/CSI Market as a senior Storage Solution Architect/CTS covering the Kansas City territory. In prior years Lloyd supported the industry accounts as a Storage Solution architect and prior to that as a Storage Software Solutions specialist during his time in the ATS organization.
Lloyd currently supports North America storage sales teams in his Storage Software Solution Architecture SME role in the Washington Systems Center team. His current focus is with IBM Cloud Private and he will be delivering and supporting sessions at Think2019, and Storage Technical University on the Value of IBM storage in this high value IBM solution a part of the IBM Cloud strategy. Lloyd maintains a Subject Matter Expert status across the IBM Spectrum Storage Software solutions. You can follow Lloyd on Twitter @ldean0558 and LinkedIn Lloyd Dean.
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In his blog post, [The Lure of Kit-Cars], fellow blogger Chuck Hollis (EMC) uses an excellent analogy delineating the differences between kit-cars you build from parts, versus fully-integrated systems that you can drive off the car dealership showroom lot. The analogy holds relatively well, as IT departments can also build their infrastructure from parts, or you can get fully-integrated systems from a variety of vendors.
Is this what your data center looks like?
Certainly, this debate is not new. In my now infamous 2007 post [Supermarkets and Specialty Shops], I explained that there were clients that preferred to get their infrastructure from a single IT supermarket, like IBM or HP, while others were lured into thinking that buying separate parts from butchers, bakers and candlestick makers and other specialty shops was somehow a better idea.
Chuck correctly explains that in the early years of the automobile industry, before major car manufacturers had mass-production assembly lines, putting a car together from parts was the only way cars were made. Today, only the few most avid enthusiasts build cars this way. The majority get cars from a single seller and drive away. In my post [Resolving the Identity Crisis], I postulated that EMC appeared to be trying to shed itself of the "disk-only specialty shop" image and over to be more like IBM. Not quite a full IT Supermarket, but perhaps more like a [Trader Joe's] premium-priced retailer.
(If you find that EMC's focus on integrated systems appears to be a 180-degree about-face from their historical focus on selling individual best-of-breed products, see my previous discussion of Chuck's contradictions in my blog post: [Is Storage the Next Confusopoly].)
While companies like EMC might be making this transition, there is a lot of resistance and inertia from the customer marketplace. I agree with Chuck, companies should not be building kit-cars or IT infrastructures from parts, certainly not from parts sold from different vendors. In my post [Talking about Solutions not Products], I explained how difficult it was to change behavior. CIOs, IT directors and managers need to think differently about their infrastructure. Let's take a quick look at some choices:
Following Chuck's argument, it makes no sense to build a "kit-car" combining Oracle/Sun servers with EMC storage. Oracle would argue it makes more sense to run on integrated systems, business logic on their "Exalogic" system, and database processing on their "Exadata". Benchmark after benchmark, however, IBM is able to demonstrate that Oracle applications and databases run faster on IBM systems. Customers that want to run Oracle applications can run either on a full Oracle stack, or a full IBM stack, and both do better than a kit-car including EMC parts.
HP has been working hard to keep up with IBM in this area. With their their partnership with Microsoft, and acquisitions of EDS, 3Com and 3PAR, they can certainly make a case for getting a full HP stack rather than a kit-car mixing HP servers with EMC disk storage. The problem is that HP is focused on a converged infrastructure for private cloud computing, but Microsoft is focused on Azure and public cloud computing. It will be interesting when these two big companies sort this out. Definitely watch this space.
If you squint your eyes and focus on the part of the world that only has x86 machines, then Dell can be seen as an IT supermarket. In my post about [Entry-Level iSCSI Offerings], I discuss how Dell's acquisition of EqualLogic was a signal that it was trying to get away from selling EMC specialty shop products, and building up its own set of offerings internally.
Cisco is new on the server scene, but has already made quite a splash. Here, I have to agree with Chuck's logic: the only time it makes sense to buy EMC disk storage at all is when it is part of an integrated "V-block". This is not really an IT supermarket situation, instead you park your car at the "Acadia Mini-Mall" and get what you need from Trader Joe's, Cisco UCS, and VMware stores.
But wait, if what you want is running VMware on Cisco servers, you might be better off with IBM System Storage N series or NetApp storage. In his blog post about [Enhanced Secure Multi-Tenancy], fellow Blogger Val Bercovici (NetApp) provides a convincing argument of why Cisco and VMware run better on an "N-block" rather than a "V-block". IBM N series provides A-SIS deduplication, and IBM Real-time Compression can provide additional capacity and performance improvements. That might be true, but whether you get your storage from EMC, NetApp or IBM, to me, you are still working with three different vendors in any case.
Of course, following Chuck's logic, it makes more sense for people with IBM servers, whether they be mainframes, POWER systems or x86 machines, to integrate these with IBM storage, IBM software and IBM services. IBM is the leading reseller of VMware, but also has a lot of business with Microsoft Hyper-V, Citrix Xen, Linux KVM, PowerVM, PR/SM and z/VM. While IBM has market leading servers, disk and tape systems, to compete for those RFP bids that just ask for one component or another, it prefers to sell fully-integrated systems, which IBM has been doing successfully since the 1950s.
Back in 2007, I mentioned how IBM's fully-integrated InfoSphere Balanced Warehouse [Trounced HP and Sun]. For business analytics, IBM offers the fully-integrated [IBM Smart Analytics Systems]. Today, IBM expanded its line of fully-integrated private cloud service delivery platforms with the announcement of the [IBM CloudBurst for on Power Systems], which does for POWER7 what the IBM CloudBurst for System x, Oracle Exalogic, or Acadia's V-block, do for x86.
IBM estimates that private clouds built on Power systems can be up to 70 percent less expensive than stand alone x86 servers.
Before he earned his PhD in Mechanical Engineering, my father was a car mechanic. I spent much of my teenage years covered in grease, helping my father assembling cars, lifting engines, and rebuilding carburetors. Certainly this was good father-son time, and I certainly did learn something in the process. Like the automobile industry, the IT industry has matured, and it makes no financial sense to build your own IT infrastructure from parts from different vendors.
For a test drive of the industry's leading integrated IT systems, see your IBM sales rep or IBM Business Partner.
Intelligent block-level disk array that virtualizes both internal and external disk storage
8 Gbps FCP and 1GbE iSCSI
IBM Storwize V7000 disk system
Real-time compression appliance for files
10GbE/1GbE CIFS and NFS
Storwize, now an IBM company
IBM Real-time Compression STN-6800 appliance
1GbE CIFS and NFS
IBM Real-time Compression STN-6500 appliance
If you think this is the first time a company like IBM has pulled shenanigans with product names like this, think again. Here are a few posts that might refresh your memory:
In my September 2006 post, [A brand by any other name...] I explain that I started blogging specifically to promote the new "IBM System Storage" product line name, part of the "IBM Systems" brand resulting from merging the "eServer" and "TotalStorage' brands.
In my January 2007 post, [When Names Change], I explain our naming convention for our disk products, including our DS family, SAN Volume Controller and N series.
In my February 2008 post, [Getting Off the Island], I cover how the x/p/i/z designations came about for our various IBM server product lines.
But what about acquisitions? When [IBM acquired Lotus Development Corporation], it kept the "Lotus" brand. New products that fit the "collaboration" function were put under the Lotus brand. I think most people can accept this approach.
But have we ever seen an existing product renamed to an acquired name?
In my post January 2009 post
[Congratulations to Ken on your QCC Milestone], I mentioned that my colleague Ken Hannigan worked on an internal project initially called "Workstation Data Save Facility" (WDSF) which was changed to "Data Facility Distributed Storage Manager" (DFDSM), then renamed to "ADSTAR Distributed Storage Manager" (ADSM), and finally renamed to the name it has today: IBM Tivoli Storage Manager (TSM).
Readers reminded me that [IBM acquired Tivoli Systems, Inc.] in 1996, so TSM could not have been an internally developed product. Ha! Wrong! Let's take a quick history lesson on how this came about:
In the late 1980s, IBM Almaden research had developed a project to backup personal computers and workstations, which they called "Workstation Data Save Facility" or WDSF.
This was turned over to our development team, which immediately discarded the code, and wrote from scratch its replacmeent, called Data Facility Distributed Storage Manager (DFDSM), named similar to the Data Facility products on the mainframe (DFP, DFHSM, DFDSS). As a member of the Data Facility family, DFDSM didn't really fit. The rest processed mainframe data sets, but DFDSM processed Windows and UNIX files. That a version of DFDSM server was available to run on the mainframe was the only connection.
Then, in the early 1990s, there were discussions of possibly splitting IBM into a bunch of smaller "Baby Blues", similar to how [AT&T was split into "Baby Bells"], and how Forbes and Goldman Sachs now want to split Microsoft into [Baby Bills]. IBM considered naming the storage spin-off as ADSTAR, which stood for "Advanced Storage and Retrieval."
Pre-emptively, IBM renamed DFDSM to "ADSTAR Distributed Storage Manager" or ADSM.
Fortunately, in 1993, IBM brought a new sheriff to town, Lou Gerstner, who quickly squashed any plans to split up IBM. He quickly realized that IBM's core strength was building integrated stacks, combining systems, software and services to solve business problems.
In 1996, IBM acquired Tivoli Systems, Inc. to expand its "Systems Management" portfolio, and renamed ADSM over to IBM Tivoli Storage Manager, since "storage management" is an essential part of "systems management". Later, IBM TotalStorage Productivity Center would be renamed to "IBM Tivoli Storage Productivity Center."
I participated in five months of painful meetings to figure out what to name our new internally-developed midrange disk system. Since it ran SAN Volume Controller software, I pushed for keeping the SVC designation somehow. We considered DS naming convention, but the new midrange product would not fit between our existing DS5000 and DS6000 numbering scheme. A marketing agency we hired came up with nonsensical names, in the spirit of product names like Celerra, Centera and CLARiiON, using name generators like [Wordoid]. Luckily, in the nick of time, IBM acquired Storwize for its compression technology, and decided that Storwize as a name was way better fit than any of the names we came up with already.
However, the new IBM Storwize V7000 midrange product had nothing in common with the appliances acquired from Storwize, the company, so to avoid confusion, the latter products were renamed to [IBM Real-time Compression]. Fellow blogger Steven Kenniston, the Storage Alchemist from Storwize fame now part of IBM from the acquisition, gives his perspective on this in his post [Storwize – What is in a Name, Really?]. While I am often critical of the names and terms IBM uses, I have to say this last set of naming decisions makes a lot of sense to me and I support it wholeheartedly.
This week, Hitachi Ltd. announced their next generation disk storage virtualization array, the Virtual Storage Platform, following on the success of its USP V line. It didn't take long for fellow blogger Chuck Hollis (EMC) to comment on this in his blog post [Hitachi's New VSP: Separating The Wheat From The Chaff]. Here are some excerpts:
"Well, we all knew that Hitachi (through HDS and HP) would be announcing some sort of refresh to their high-end storage platform sooner or later.
As EMC is Hitachi's only viable competitor in this part of the market, I think people are expecting me to say something.
If you're a high-end storage kind of person, your universe is basically a binary star: EMC and Hitachi orbiting each other, with the interesting occasional sideshow from other vendors trying to claim relevance in this space."
Chuck implies that neither Hewlett-Packard (HP) nor Hitachi Data Systems (HDS) as vendors provide any value-add from the box manufactured by Hitachi Ltd. so combines them into a single category. I suspect the HP and HDS folks might disagree with that opinion.
When I reminded Chuck that IBM was also a major player in the high-end disk space, his response included the following gem:
"Many of us in the storage industry believe that IBM currently does not field a competitive high-end storage platform. IDC market share numbers bear out this assertion, as you probably know."
While Chuck is certainly entitled to his own beliefs and opinions, believing the world is flat does not make it so. Certainly, I doubt IDC or any other market research firm has put out a survey asking "Do you think IBM offers a competitive high-end disk storage platform?" Of course, if Chuck is basing his opinion on anecdotal conversations with existing EMC customers, I can certainly see how he might have formed this misperception. However, IDC market share numbers don't support Chuck's assertion at all.
There is no industry-standard definition of what is a "high-end" or "enterprise-class" disk system. Some define high-end as having the option for mainframe attachment via ESCON and/or FICON protocol. Others might focus on features, functionality, scalability and high 99.999+ percent availability. Others insist high-end requires block-oriented protocols like FC and iSCSI, rather than file-based protocols like NAS and CIFS.
For the most demanding mission-critical mix of random and sequential workloads, IBM offers the [IBM System Storage DS8000 series] high-end disk system which connects to mainframes and distributed servers, via FCP and FICON attachment, and supports a variety of drive types and RAID levels. The features that HP and HDS are touting today for the VSP are already available on the IBM DS8000, including sub-LUN automatic tiering between Solid-State drives and spinning disk, called [Easy Tier], thin provisioning, wide striping, point-in-time copies, and long distance synchronous and asynchronous replication.
There are lots of analysts that track market share for the IT storage industry, but since Chuck mentions [IDC] specifically, I reviewed the most recent IDC data, published a few weeks ago in their "IDC Worldwide Quarter Disk Storage Tracker" for 2Q 2010, representing April 1 to June 30, 2010 sales. Just in case any of the rankings have changed over time, I also looked at the previous four quarters: 2Q 2009, 3Q 2009, 4Q 2009 and 1Q 2010.
(Note: IDC considers its analysis proprietary, out of respect for their business model I will not publish any of the actual facts and figures they have collected. If you would like to get any of the IDC data to form your own opinion, contact them directly.)
In the case of IDC, they divide the disk systems into three storage classes: entry-level, midrange and high-end. Their definition of "high-end" is external RAID-protected disk storage that sells for $250,000 USD or more, representing roughly 25 to 30 percent of the external disk storage market overall. Here are IDC's rankings of the four major players for high-end disk systems:
By either measure of market share, units (disk systems) or revenue (US dollars), IDC reports that IBM high-end disk outsold both HDS and HP combined. This has been true for the past five quarters. If a smaller start-up vendor has single digit percent market share, I could accept it being counted as part of Chuck's "occasional sideshow from other vendors trying to claim relevance", but IBM high-end disk has consistently had 20 to 30 percent market share over the past five quarters!
Not all of these high-end disk systems are connected to mainframes. According to IDC data, only about 15 to 25 percent of these boxes are counted under their "Mainframe" topology.
Chuck further writes:
"It's reasonable to expect IBM to sell a respectable amount of storage with their mainframes using a protocol of their own design -- although IBM's two competitors in this rather proprietary space (notably EMC and Hitachi) sell more together than does IBM."
The IDC data doesn't support that claim either, Chuck. By either measure of market share, units (disk systems) or revenue (US dollars), IDC reports that IBM disk for mainframes outsold all other vendors (including EMC, HDS, and HP) combined. And again, this has been true for the past five quarters. Here is the IDC ranking for mainframe disk storage:
IBM has over 50 percent market share in this case, primarily because IBM System Storage DS8000 is the industry leader in mainframe-related features and functions, and offers synergy with the rest of the z/Architecture stack.
So Chuck, I am not picking a fight with you or asking you to retract or correct your blog post. Your main theme, that the new VSP presents serious competition to EMC's VMAX high-end disk arrays, is certainly something I can agree with. Congratulations to HDS and HP for putting forth what looks like a viable alternative to EMC's VMAX.
To learn more about IBM's upcoming products, register for next week's webcast "Taming the Information Explosion with IBM Storage" featuring Dan Galvan, IBM Vice President, and Steve Duplessie, Senior Analyst and Founder of Enterprise Storage Group (ESG).
Last week, in Computer Technology Review's article [Tiering: Scale Up? Scale Out? Do Both], Mark Ferelli interviews fellow blogger Hu Yoshida, CTO of Hitachi Data Systems (HDS). Here's an excerpt:
"MF/CTR: A global cache should be required to implement that common pool that you’re talking about going across all tiers.
Hu/HDS: Right. So that is needed to get to all the resources. Now with our system, we can also attach external storage behind it for capacity so that as the storage ages out or becomes less active we can move it to the external storage. They would certainly have less performance capability, but you don’t need it for the stale data that we’re aging down. Right now we’re the only vendor that can provide this type of tiering.
If you look at other people who do virtualization like IBM’s SVC, the SVC has no storage within it because it’s sitting so if you attach any storage behind it, there is some performance degradation because you have this appliance sitting in front. That appliance is also very limited in cache and very limited in the number of storage boards on it. It cannot really provide you additional performance than what is attached behind it. And in fact, it will always degrade what is attached behind it because it’s not storage, where as our USP is storage and it has a global cache and it has thousands of port connections, load balancing and all that. So our front end can enhance existing storage that sits behind it."
This is not the first time I have had to correct Hu and others of misperceptions of IBM's SAN Volume Controller (SVC). This month marks my four year "blogoversary", and I seem to spend a large portion of my blogging time setting the record straight. Here are just a few of my favorite posts setting the record straight on SVC back in 2007:
Since day 1, SAN Volume Controllers has focused primarily on external storage. Initially, the early models had just battery-protected DRAM cache memory, but the most recent model of the SVC, the 2145-CF8, adds support for internal SLC NAND flash solid state drives. To fully appreciate how SVC can help improve the performance of the disks that are managed, I need to use some visual aids.
In this first chart, we look at a 70/30/50 workload. This indicates that 70 percent of the IOPS are reads, 30 percent writes, and 50 percent can be satisfied as cache hits directly from the SVC. For the reads, this means that 50 percent are read-hits satisfied from SVC DRAM cache, and 50 percent are read-miss that have to get the data from the managed disk, either from the managed disk's own cache, or from the actual spinning drives inside that managed disk array.
For writes, all writes are cache-hits, but some of them will be destaged to the managed disk. Typically, we find that a third of writes are over-written before this happens, so only two-thirds are written down to managed disk.
In this example, the SVC reduced the burden of the managed disk from 100,000 IOPS down to 55,000, which is 35,000 reads and 20,000 writes. Some have argued against putting one level of cache (SVC) in front of another level of cache (managed disk arrays). However, CPU processor designers have long recognized the value of hierarchical cache with L1, L2, L3 and sometimes even L4 caches. The cache-hits on SVC are faster than most disk system's cache-hits.
This is a Ponder curve, mapping millisecond response (MSR) times for different levels of I/O per second, named after the IBM scientist John Ponder that created them. Most disk array vendors will publish similar curves for each of their products. In this case, we see that 100,000 IOPS would cause a 25 millisecond response (MSR) time, but when the load is reduced to 55,000 IOPS, the average response time drops to only 7 msec.
To be fair, the SVC does introduce 0.06 msec of additional latency on read-misses, so let's call this 7.06 msec. This tiny amount of latency could be what Hu Yoshida was referring to when he said there was "some performance degradation". There are other storage virtualization products in the market that do not provide caching to boost performance, but rather just map incoming requests to outgoing requests, and these can indeed slow down every I/O they process. Perhaps Hu was thinking of those instead of IBM's SVC when he made his comments.
Of course, not all workloads are 70/30/50, and not every disk array is driven to its maximum capability, so your mileage may vary. As we slide down the left of the curve where things are flatter, the improvement in performance lowers.
IOPS before SVC
IOPS after SVC
MSR before SVC
MSR after SVC
Hitachi's offerings, including the HDS USP-V, USP-VM and their recently announced Virtual Storage Platform (VSP) sold also by HP under the name P9500, have similar architecture to the SVC and can offer similar benefits, but oddly the Hitachi engineers have decided to treat externally attached storage as second-class citizens instead. Hu mentions data that "ages out or becomes less active we can move it to the external storage." IBM has chosen not to impose this "caste" system onto its design of the SAN Volume Controller.
The SVC has been around since 2003, before the USP-V came to market, and has sold over 20,000 SVC nodes over the past seven years. The SVC can indeed improve performance of managed disk systems, in some cases by a substantial amount. The 0.06 msec latency on read-miss requests represents less than 1 percent of total performance in production workloads. SVC nearly always improves performance, and in the worst case, provides same performance but with added functionality and flexibility. For the most part, the performance boost comes as a delightful surprise to most people who start using the SVC.
To learn more about IBM's upcoming products and how IBM will lead in storage this decade, register for next week's webcast "Taming the Information Explosion with IBM Storage" featuring Dan Galvan, IBM Vice President, and Steve Duplessie, Senior Analyst and Founder of Enterprise Storage Group (ESG).
In my presentations in Australia and New Zealand, I mentioned that people were re-discovering the benefits of removable media. While floppy diskettes were convenient way of passing information from one person to another, they unfortunately did not have enough capacity. In today's world, you may need Gigabytes or Terabytes of re-writeable storage with a file system interface that can easily be passed from one person to another. In this post, I explore three options.
(FCC Disclaimer: I work for IBM, and IBM has no business relationship with Cirago at the time of this writing. Cirago has not paid me to mention their product, but instead provided me a free loaner that I promised to return to them after my evaluation is completed. This post should not be considered an endorsement for Cirago's products. List prices for Cirago and IBM products were determined from publicly available sources for the United States, and may vary in different countries. The views expressed herein may not necessarily reflect the views and opinions of either IBM or Cirago.)
I took a few photos so you can see what exactly this device looks like. Basically, it is a plastic box that holds a single naked disk drive. It has four little rubber feet so that it does not slip on your desk surface.
The inside is quite simple. The power and SATA connections match those of either a standard 3.5 inch drive, or the smaller form factor (SFF) 2.5 inch drive. However, to my dismay, it does not handle EIDE drives which I have a ton of. After taking apart six different computer systems, I found only one had SATA drives for me to try this unit out with.
The unit comes with a USB cable and AC/DC power adapter. In my case, I found the USB 3.0 cable too short for my liking. My tower systems are under my desk, but I like keeping docking stations like this on the top of the desk, within easy reach, but that wasn't going to happen because the USB cable was not long enough.
Instead, I ended up putting it half-way in between, behind my desk, sitting on another spare system. Not ideal, but in theory there are USB-extension cables that probably could fix this.
Here it is with the drive inside. I had a 3.5 inch Western Digital [1600AAJS drive] 160 GB, SATA 3 Gbps, 8 MB Cache, 7200 RPM.
To compare the performance, I used a dual-core AMD [Athlon X2] system that I had built for my 2008 [One Laptop Per Child] project. To compare the performance, I ran with the drive externally in the Cirago docking station, then ran the same tests with the same drive internally on the native SATA controller. Although the Cirago documentation indicated that Windows was required, I used Ubuntu Linux 10.04 LTS just fine, using the flexible I/O [fio] benchmarking tool against an ext3 file system.
Sequential Write - a common use for external disk drive is backup.
Random read - randomly read files ranging from 5KB to 10MB in size.
Random mixed - randomly read/write files (50/50 mix) ranging from 5KB to 10MB in size.
Random Mixed (50/50)
Latency (msec) read
Latency (msec) write
Bandwidth (KB/s) read
Bandwidth (KB/s) write
For sequential write, the Cirago performed well, only about 15 percent slower than native SATA. For random workloads, however, it was 30-40 percent slower. If you are wondering why I did not get USB 3.0 speeds, there are several factors involved here. First, with overheads, 5 Gbps USB 3.0 is expected to get only about 400 MB/sec. My SATA 2.0 controller maxes out at 375 MB/sec, and my USB 2.0 ports on my system are rated for 57 MB/sec, but with overheads will only get 20-25 MB/sec. Most spinning drives only get 75 to 110 MB/sec. Even solid-state drives top out at 250 MB/sec for sustained activity. Despite all that, my internal SATA drive only got 16 MB/sec, and externally with the Cirago 14 MB/sec in sustained write activity.
Here is the mess that is inside my system. The slot for drive 2 was blocked by cables, memory chips and the heat sink for my processor. It is possible to damage a system just trying to squeeze between these obstacles.
However, the point of this post is "removable media". Having to open up the case and insert the second drive and wire it up to the correct SATA port was a pain, and certainly a more difficult challenge than the average PC user wishes to tackle.
Price-wise, the Cirago lists for $49 USD, and the 160GB drive I used lists for $69, so the combination $118 is about what you would pay for a fully integrated external USB drive. However, if you had lots of loose drives, then this could be more convenient and start to save you some money.
IBM RDX disk backup system
Another problem with the Cirago approach is that the disk drives are naked, with printed circuit board (PCB) exposed. When not in the docking station, where do you put your drive? Did you keep the [anti-static ESD bag] that it came in when you bought it? And once inside the bag, now what? Do you want to just stack it up in a pile with your other pieces of equipment?
To solve this, IBM offers the RDX backup system. These are fully compatible with other RDX sytems from Dell, HP, Imation, NEC, Quantum, and Tandberg Data. The concept is to have a docking station that takes removable, rugged plastic-coated disk-enclosed cartridges. The docking station can be part of the PC itself, similar to how CD/DVD drives are installed, or as a stand-alone USB 2.0 system, capable of processing data up to 25 MB/sec.
The idea is not new, about 10 years ago we had [Iomega "zip" drives] that offered disk-enclosed cartridges with capacities of 100, 250 and 750MB in size. Iomega had its fair share of problems with the zip drive, which were ranked in 2006 as the 15th worst technology product of all time, and were eventually were bought out by EMC two years later (as if EMC has not had enough failures on its own!)
The problem with zip drives was that they did not hold as much as CD or DVD media, and were more expensive. By comparison, IBM RDX cartridges come in 160GB to 750GB in size, at list prices starting at $127 USD.
IBM LTO tape with Long-Term File System
Removable media is not just for backup. Disk cartridges, like the IBM RDX above, had the advantage of being random access, but most tape are accessed sequentially. IBM has solved this also, with the new IBM Long Term File System [LTFS], available for LTO-5 tape cartridges.
With LFTS, the LTO-5 tape cartridge now can act as a super-large USB memory stick for passing information from one person to the next. The LTO-5 cartridge can handle up to 3TB of compressed data at up to SAS speeds of 140 MB/sec. An LTO-5 tape cartridge lists for only $87 USD.
The LTO-5 drives, such as the IBM [TS2250 drive] can read LTO-3, LTO-4 and LTO-5cartridges, and can write LTO-4 and LTO-5 cartridges, in a manner that is fully compatible with LTO drives from HP or Quantum. LTO-3, LTO-4 and LTO-5 cartridges are available in WORM or rewriteable formats. LTO-4 and LTO-5 cartridges can be encrypted with 256-bit AES built-in encryption. With three drive manufacturers, and seven cartridge manufacturers, there is no threat of vendor lock-in with this approach.
These three options offer various trade-offs in price, performance, security and convenience. Not surprisingly, tape continues to be the cheapest option.