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Tony Pearson is a Master Inventor and Senior IT Specialist for the IBM System Storage product line at the
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author of the Inside System Storage series of books. This blog is for the open exchange of ideas relating to storage and storage networking hardware, software and services. You can also follow him on Twitter @az990tony.
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Well, it's Tuesday again, but this time, today we had our third big storage launch of 2009! A lot got announced today as part of IBM's big "Dynamic Infrastructure" marketing campaign. I will just focus on the
disk-related announcements today:
IBM System Storage DS8700
IBM adds a new model to its DS8000 series with the
[IBM System Storage DS8700]. Earlier this month, fellow blogger and arch-nemesis Barry Burke from EMC posted [R.I.P DS8300] on this mistaken assumption that the new DS8700 meant that DS8300 was going away, or that anyone who bought a DS8300 recently would be out of luck. Obviously, I could not respond until today's announcement, as the last thing I want to do is lose my job disclosing confidential information. BarryB is wrong on both counts:
IBM will continue to sell the DS8100 and DS8300, in addition to the new DS8700.
Clients can upgrade their existing DS8100 or DS8300 systems to DS8700.
BarryB's latest post [What's In a Name - DS8700] is fair game, given all the fun and ridicule everyone had at his expense over EMC's "V-Max" name.
So the DS8700 is new hardware with only 4 percent new software. On the hardware side, it uses faster POWER6 processors instead of POWER5+, has faster PCI-e buses instead of the RIO-G loops, and faster four-port device adapters (DAs) for added bandwidth between cache and drives. The DS8700 can be ordered as a single-frame dual 2-way that supports up to 128 drives and 128GB of cache, or as a dual 4-way, consisting of one primary frame, and up to four expansion frames, with up to 384GB of cache and 1024 drives.
Not mentioned explicitly in the announcements were the things the DS8700 does not support:
ESCON attachment - Now that FICON is well-established for the mainframe market, there is no need to support the slower, bulkier ESCON options. This greatly reduced testing effort. The 2-way DS8700 can support up to 16 four-port FICON/FCP host adapters, and the 4-way can support up to 32 host adapters, for a maximum of 128 ports. The FICON/FCP host adapter ports can auto-negotiate between 4Gbps, 2Gbps and 1Gbps as needed.
LPAR mode - When IBM and HDS introduced LPAR mode back in 2004, it sounded like a great idea the engineers came up with. Most other major vendors followed our lead to offer similar "partitioning". However, it turned out to be what we call in the storage biz a "selling apple" not a "buying apple". In other words, something the salesman can offer as a differentiating feature, but that few clients actually use. It turned out that supporting both LPAR and non-LPAR modes merely doubled the testing effort, so IBM got rid of it for the DS8700.
Update: I have been reminded that both IBM and HDS delivered LPAR mode within a month of each other back in 2004, so it was wrong for me to imply that HDS followed IBM's lead when obviously development happened in both companies for the most part concurrently prior to that. EMC was late to the "partition" party, but who's keeping track?
Initial performance tests show up to 50 percent improvement for random workloads, and up to 150 percent improvement for sequential workloads, and up to 60 percent improvement in background data movement for FlashCopy functions. The results varied slightly between Fixed Block (FB) LUNs and Count-Key-Data (CKD) volumes, and I hope to see some SPC-1 and SPC-2 benchmark numbers published soon.
The DS8700 is compatible for Metro Mirror, Global Mirror, and Metro/Global Mirror with the rest of the DS8000 series, as well as the ESS model 750, ESS model 800 and DS6000 series.
New 600GB FC and FDE drives
IBM now offers [600GB drives] for the DS4700 and DS5020 disk systems, as well as the EXP520 and EXP810 expansion drawers. In each case, we are able to pack up to 16 drives into a 3U enclosure.
Personally, I think the DS5020 should have been given a DS4xxx designation, as it resembles the DS4700
more than the other models of the DS5000 series. Back in 2006-2007, I was the marketing strategist for IBM System Storage product line, and part of my job involved all of the meetings to name or rename products. Mostly I gave reasons why products should NOT be renamed, and why it was important to name the products correctly at the beginning.
IBM System Storage SAN Volume Controller hardware and software
Fellow IBM master inventory Barry Whyte has been covering the latest on the [SVC 2145-CF8 hardware]. IBM put out a press release last week on this, and today is the formal announcement with prices and details. Barry's latest post
[SVC CF8 hardware and SSD in depth] covers just part of the entire
The other part of the announcement was the [SVC 5.1 software] which can be loaded
on earlier SVC models 8F2, 8F4, and 8G4 to gain better performance and functionality.
To avoid confusion on what is hardware machine type/model (2145-CF8 or 2145-8A4) and what is software program (5639-VC5 or 5639-VW2), IBM has introduced two new [Solution Offering Identifiers]:
5465-028 Standard SAN Volume Controller
5465-029 Entry Edition SAN Volume Controller
The latter is designed for smaller deployments, supports only a single SVC node-pair managing up to
150 disk drives, available in Raven Black or Flamingo Pink.
EXN3000 and EXP5060 Expansion Drawers
IBM offers the [EXN3000 for the IBM N series]. These expansion drawers can pack 24 drives in a 4U enclosure. The drives can either be all-SAS, or all-SATA, supporting 300GB, 450GB, 500GB and 1TB size capacity drives.
The [EXP5060 for the IBM DS5000 series] is a high-density expansion drawer that can pack up to 60 drives into a 4U enclosure. A DS5100 or DS5300
can handle up to eight of these expansion drawers, for a total of 480 drives.
Pre-installed with Tivoli Storage Productivity Center Basic Edition. Basic Edition can be upgraded with license keys to support Data, Disk and Standard Edition to extend support and functionality to report and manage XIV, N series, and non-IBM disk systems.
Pre-installed with Tivoli Key Lifecycle Manager (TKLM). This can be used to manage the Full Disk Encryption (FDE) encryption-capable disk drives in the DS8000 and DS5000, as well as LTO and TS1100 series tape drives.
IBM Tivoli Storage FlashCopy Manager v2.1
The [IBM Tivoli Storage FlashCopy Manager V2.1] replaces two products in one. IBM used
to offer IBM Tivoli Storage Manager for Copy Services (TSM for CS) that protected Windows application data, and IBM Tivoli Storage Manager for Advanced Copy Services (TSM for ACS) that protected AIX application data.
The new product has some excellent advantages. FlashCopy Manager offers application-aware backup of LUNs containing SAP, Oracle, DB2, SQL server and Microsoft Exchange data. It can support IBM DS8000, SVC and XIV point-in-time copy functions, as well as the Volume Shadow Copy Services (VSS) interfaces of the IBM DS5000, DS4000 and DS3000 series disk systems. It is priced by the amount of TB you copy, not on the speed or number of CPU processors inside the server.
Don't let the name fool you. IBM FlashCopy Manager does not require that you use Tivoli Storage Manager (TSM) as your backup product. You can run IBM FlashCopy Manager on its own, and it will manage your FlashCopy target versions on disk, and these can be backed up to tape or another disk using any backup product. However, if you are lucky enough to also be using TSM, then there is optional integration that allows TSM to manage the target copies, move them to tape, inventory them in its DB2 database, and provide complete reporting.
Yup, that's a lot to announce in one day. And this was just the disk-related portion of the launch!
Have you ever noticed that sometimes two movies come out that seem eerily similar to each other, released by different studios within months or weeks of each other? My sister used to review film scripts for a living, she would read ten of them and have to pick her top three favorites, and tells me that scripts for nearly identical concepts came all the time. Here are a few of my favorite examples:
1994: [Wyatt Earp] and [Tombstone] were Westerns recounting the famed gunfight at the O.K. Corral. Tombstone, Arizona is near Tucson, and the gunfight is recreated fairly often for tourists.
1998: [Armageddon] and [Deep Impact] were a pair of disaster movies dealing with a large rock heading to destroy all life on earth. I was in Mazatlan, Mexico to see the latter, dubbed in Spanish as "Impacto Profundo".
1998: [A Bug's Life] and [Antz] were computer-animated tales of the struggle of one individual ant in an ant colony.
2000: [Mission to Mars] and [Red Planet] were sci-fi pics exploring what a manned mission to our neighboring planet might entail.
This is different than copy-cat movies that are re-made or re-imagined many years later based on the previous successes of an original. Ever since my blog post [VPLEX: EMC's Latest Wheel is Round] in 2010 comparing EMC's copy-cat product that came our seven years after IBM's SAN Volume Controller (SVC), I've noticed EMC doesn't talk about VPLEX that much anymore.
This week, IBM announced [XIV Gen3 Solid-State Drive support] and our friends over at EMC announced [VFCache SSD-based PCIe cards]. Neither of these should be a surprise to anyone who follows the IT industry, as IBM had announced its XIV Gen3 as "SSD-Ready" last year specifically for this purpose, and EMC has been touting its "Project Lightning" since last May.
Fellow blogger Chuck Hollis from EMC has a blog post [VFCache means Very Fast Cache indeed] that provides additional detail. Chuck claims the VFCache is faster than popular [Fusion-IO PCIe cards] available for IBM servers. I haven't seen the performance spec sheets, but typically SSD is four to five times slower than the DRAM cache used in the XIV Gen3. The VFCache's SSD is probably similar in performance to the SSD supported in the IBM XIV Gen3, DS8000, DS5000, SVC, N series, and Storwize V7000 disk systems.
Nonetheless, I've been asked my opinions on the comparison between these two announcements, as they both deal with improving application performance through the use of Solid-State Drives as an added layer of read cache.
(FTC Disclosure: I am both a full-time employee and stockholder of the IBM Corporation. The U.S. Federal Trade Commission may consider this blog post as a paid celebrity endorsement of IBM servers and storage systems. This blog post is based on my interpretation and opinions of publicly-available information, as I have no hands-on access to any of these third-party PCIe cards. I have no financial interest in EMC, Fusion-IO, Texas Memory Systems, or any other third party vendor of PCIe cards designed to fit inside IBM servers, and I have not been paid by anyone to mention their name, brands or products on this blog post.)
The solutions are different in that IBM XIV Gen3 the SSD is "storage-side" in the external storage device, and EMC VFCache is "server-side" as a PCI Express [PCIe] card. Aside from that, both implement SSD as an additional read cache layer in front of spinning disk to boost performance. Neither is an industry first, as IBM has offered server-side SSD since 2007, and IBM and EMC have offered storage-side SSD in many of their other external storage devices. The use of SSD as read cache has already been available in IBM N series using [Performance Accelerator Module (PAM)] cards.
IBM has offered cooperative caching synergy between its servers and its storage arrays for some time now. The predecessor to today's POWER7-based were the iSeries i5 servers that used PCI-X IOP cards with cache to connect i5/OS applications to IBM's external disk and tape systems. To compete in this space, EMC created their own PCI-X cards to attach their own disk systems. In 2006, IBM did the right thing for our clients and fostered competition by entering in a [Landmark agreement] with EMC to [license the i5 interfaces]. Today, VIOS on IBM POWER systems allows a much broader choice of disk options for IBM i clients, including the IBM SVC, Storwize V7000 and XIV storage systems.
Can a little SSD really help performance? Yes! An IBM client running a [DB2 Universal Database] cluster across eight System x servers was able to replace an 800-drive EMC Symmetrix by putting eight SSD Fusion-IO cards in each server, for a total of 64 Solid-State drives, saving money and improving performance. DB2 has the Data Partitioning Feature that has multi-system DB2 configurations using a Grid-like architecture similar to how XIV is designed. Most IBM System x and BladeCenter servers support internal SSD storage options, and many offer PCIe slots for third-party SSD cards. Sadly, you can't do this with a VFCache card, since you can have only one VFCache card in each server, the data is unprotected, and only for ephemeral data like transaction logs or other temporary data. With multiple Fusion-IO cards in an IBM server, you can configure a RAID rank across the SSD, and use it for persistent storage like DB2 databases.
Here then is my side-by-side comparison:
IBM XIV Gen3 SSD Caching
Selected x86-based models of Cisco UCS, Dell PowerEdge, HP ProLiant DL, and IBM xSeries and System x servers
All of these, plus any other blade or rack-optimized server currently supported by XIV Gen3, including Oracle SPARC, HP Titanium, IBM POWER systems, and even IBM System z mainframes running Linux
Operating System support
Linux RHEL 5.6 and 5.7, VMware vSphere 4.1 and 5.0, and Windows 2008 x64 and R2.
All of these, plus all the other operating systems supported by XIV Gen3, including AIX, IBM i, Solaris, HP-UX, and Mac OS X
FCP and iSCSI
Vendor-supplied driver required on the server
Yes, the VFCache driver must be installed to use this feature.
No, IBM XIV Gen3 uses native OS-based multi-pathing drivers.
External disk storage systems required
None, it appears the VFCache has no direct interaction with the back-end disk array, so in theory the benefits are the same whether you use this VFCache card in front of EMC storage or IBM storage
XIV Gen3 is required, as the SSD slots are not available on older models of IBM XIV.
Shared disk support
No, VFCache has to be disabled and removed for vMotion to take place.
Yes! XIV Gen3 SSD caching shared disk supports VMware vMotion and Live Partition Mobility.
Support for multiple servers
An advantage of the XIV Gen3 SSD caching approach is that the cache can be dynamically allocated to the busiest data from any server or servers.
Support for active/active server clusters
Aware of changes made to back-end disk
No, it appears the VFCache has no direct interaction with the back-end disk array, so any changes to the data on the box itself are not communicated back to the VFCache card itself to invalidate the cache contents.
None identified. However, VFCache only caches blocks 64KB or smaller, so any sequential processing with larger blocks will bypass the VFCache.
Yes! XIV algorithms detect sequential access and avoid polluting the SSD with these blocks of data.
Number of SSD supported
One, which seems odd as IBM supports multiple Fusion-IO cards for its servers. However, this is not really a single point of failure (SPOF) as an application experiencing a VFCache failure merely drops down to external disk array speed, no data is lost since it is only read cache.
6 to 15 (one per XIV module) for high availability.
Pin data in SSD cache
Yes, using split-card mode, you can designate a portion of the 300GB to serve as Direct-attached storage (DAS). All data written to the DAS portion will be kept in SSD. However, since only one card is supported per server and the data is unprotected, this should only be used for ephemeral data like logs and temp files.
No, there is no option to designate an XIV Gen3 volume to be SSD-only. Consider using Fusion-IO PCIe card as a DAS alternative, or another IBM storage system for that requirement.
Pre-sales Estimating tools
Yes! CDF and Disk Magic tools are available to help cost-justify the purchase of SSD based on workload performance analysis.
IBM has the advantage that it designs and manufactures both servers and storage, and can design optimal solutions for our clients in that regard.
From New York, Rolf went to London, Paris, Madrid, Morocco, Cairo, South Africa, Bangkok Thailand, Malaysia, Singapore, New Zealand, Australia, and then back to United States. I was hoping to run into him while I was in Australia and New Zealand last month, but our schedules did not line up.
Travelingwithout baggage is more than just a convenience, it is a metaphor for the philosophy that we should keep only what we need, and leave behind what we don't. This was the approach taken by IBM in the design of the IBM Storwize V7000 midrange disk system.
The IBM Storwize V7000 disk system consists of 2U enclosures. Controller enclosures have dual-controllers and drives. Expansion enclosures have just drives. Enclosures can have either 24 smaller form factor (SFF) 2.5-inch drives, or twelve larger 3.5-inch drives. A controller enclosure can be connected up to nine expansion enclosures.
The drives are all connected via 6 Gbps SAS, and come in a variety of speeds and sizes: 300GB Solid-State Drive (SSD); 300GB/450GB/600GB high-speed 10K RPM; and 2TB low-speed 7200 RPM drives. The 12-bay enclosures can be intermixed with 24-bay enclosures on the same system, and within an enclosure different speeds and sizes can be intermixed. A half-rack system (20U) could hold as much as 480TB of raw disk capacity.
This new system, freshly designed entirely within IBM, competes directly against systems that carry a lot of baggage, including the HDS AMS, HP EVA, an EMC CLARiiON CX4 systems. Instead, we decided to keep the what we wanted from our other successful IBM products.
Inspired by our successful XIV storage system, IBM has developed a web-based GUI that focuses on ease-of-use. This GUI uses the latest HTML5 and dojo widgets to provide an incredible user experience.
Borrowed from our IBM DS8000 high-end disk systems, state-of-the-art device adapters provide 6 Gbps SAS connectivity with a variety of RAID levels: 0, 1, 5, 6, and 10.
From our SAN Volume Controller, the embedded [ SVC 6.1 firmware] provides all of the features and functions normally associated with enterprise-class systems, including Easy Tier sub-LUN automated tiering between Solid-State Drives and Spinning disk, thin provisioning, external disk virtualization, point-in-time FlashCopy, disk mirroring, built-in migration capability, and long-distance synchronous and asynchronous replication.
Finally, the various "internal NDA" that kept me from publishing this sooner have expired, so now I have the long-awaited [Inside System Storage: Volume II], documenting IBM's transformation in its storage strategy, including behind-the-scenes commentary about IBM's acquisitions of XIV and Diligent. Available initially in paperback form. I am still working on the hard cover and eBook editions.
For those who have not yet read my first book, Inside System Storage: Volume I, it is still available from my publisher Lulu, in [hard cover], [paperback] and [eBook] editions.
IBM System Storage DS8800
A lesson IBM learned long ago was not to make radical changes to high-end disk systems, as clients who run mission-critical applications are more concerned about reliability, availability and serviceability than they are performance or functionality. Shipping any product before it was ready meant painfully having to fix the problems in the field instead.
(EMC apparently is learning this same lesson now with their VMAX disk system. Their Engenuity code from Symmetrix DMX4 was ported over to new CLARiiON-based hardware. With several hundred boxes in the field, they have already racked up over 150 severity 1 problems, roughly half of these resulted in data loss or unavailability issues. For the sake of our mutual clients that have both IBM servers and EMC disk, I hope they get their act together soon.)
To avoid this, IBM made incremental changes to the successful design and architecture of its predecessors. The new DS8800 shares 85 percent of the stable microcode from the DS8700 system. Functions like Metro Mirror, Global Mirror, and Metro/Global Mirror, are compatible with all of the previous models of the DS8000 series, as well as previous models of the IBM Enterprise Storage Server (ESS) line.
The previous models of DS8000 series were designed to take in cold air from both front and back, and route the hot air out the top, known as chimney design. However, many companies are re-arranging their data centers into separate cold aisles and hot aisles. The new DS8800 has front-to-back cooling to help accommodate this design.
My colleague Curtis Neal would call the rest of this a "BFD" announcement, which of course stands for "Bigger, Faster and Denser". The new DS8800 scales-up to more drives than its DS8700 predecessor, and can scale-out from a single-frame 2-way system to a multi-frame 4-way system. IBM has upgraded to faster 5GHz POWER6+ processors, with dual-core 8 Gbps FC and FICON host adapters, 8 Gbps device adapters, and 6 Gbps SAS connectivity to smaller form factor (SFF) 2.5-inch SAS drives. IBM Easy Tier will provide sub-LUN automated tiering between Solid-State Drives and spinning disk. The denser packaging with SFF drives means that we can pack over 1000 drives in only three frames, compared to five frames required for the DS8700.
The [IBM System Storage SAN Volume Controller] software release v6.1 brings Easy Tier sub-LUN automated tiering to the rest of the world. IBM Easy Tier moves the hottest, most active extents up to Solid-State Drives (SSD) and moves the coldest, least active down to spinning disk. This works whether the SSD is inside the SVC 2145-CF8 nodes, or in the managed disk pool.
Tired of waiting for EMC to finally deliver FAST v2 for your VMAX? It has been 18 months since they first announced that someday they would have sub-LUN automatic tiering. What is taking them so long? Why not virtualize your VMAX with SVC, and you can have it sooner!
SVC 6.1 also upgrades to a sexy new web-based GUI, which like the one for the IBM Storwize V7000, is based on the latest HTML5 and dojo widget standards. Inspired by the popular GUI from the IBM XIV Storage System, this GUI has greatly improved ease-of-use.
Here I am, day 11 of a 17-day business trip, on my last leg of the trip this week, in Kuala Lumpur in Malaysia. I have been flooded with requests to give my take on EMC's latest re-interpretation of storage virtualization, VPLEX.
I'll leave it to my fellow IBM master inventor Barry Whyte to cover the detailed technical side-by-side comparison. Instead, I will focus on the business side of things, using Simon Sinek's Why-How-What sequence. Here is a [TED video] from Garr Reynold's post
[The importance of starting from Why].
Let's start with the problem we are trying to solve.
Problem: migration from old gear to new gear, old technology to new technology, from one vendor to another vendor, is disruptive, time-consuming and painful.
Given that IT storage is typically replaced every 3-5 years, then pretty much every company with an internal IT department has this problem, the exception being those companies that don't last that long, and those that use public cloud solutions. IT storage can be expensive, so companies would like their new purchases to be fully utilized on day 1, and be completely empty on day 1500 when the lease expires. I have spoken to clients who have spent 6-9 months planning for the replacement or removal of a storage array.
A solution to make the data migration non-disruptive would benefit the clients (make it easier for their IT staff to keep their data center modern and current) as well as the vendors (reduce the obstacle of selling and deploying new features and functions). Storage virtualization can be employed to help solve this problem. I define virtualization as "technology that makes one set of resources look and feel like a different set of resources, preferably with more desirable characteristics.". By making different storage resources, old and new, look and feel like a single type of resource, migration can be performed without disrupting applications.
Before VPLEX, here is a breakdown of each solution:
Non-disruptive tech refresh, and a unified platform to provide management and functionality across heterogeneous storage.
Non-disruptive tech refresh, and a unified platform to provide management and functionality between internal tier-1 HDS storage, and external tier-2 heterogeneous storage.
Non-disruptive tech refresh, with unified multi-pathing driver that allows host attachment of heterogeneous storage.
New in-band storage virtualization device
Add in-band storage virtualization to existing storage array
New out-of-band storage virtualization device with new "smart" SAN switches
SAN Volume Controller
HDS USP-V and USP-VM
For IBM, the motivation was clear: Protect customers existing investment in older storage arrays and introduce new IBM storage with a solution that allows both to be managed with a single set of interfaces and provide a common set of functionality, improving capacity utilization and availability. IBM SAN Volume Controller eliminated vendor lock-in, providing clients choice in multi-pathing driver, and allowing any-to-any migration and copy services. For example, IBM SVC can be used to help migrate data from an old HDS USP-V to a new HDS USP-V.
With EMC, however, the motivation appeared to protect software revenues from their PowerPath multi-pathing driver, TimeFinder and SRDF copy services. Back in 2005, when EMC Invista was first announced, these three software represented 60 percent of EMC's bottom-line profit. (Ok, I made that last part up, but you get my point! EMC charges a lot for these.)
Back in 2006, fellow blogger Chuck Hollis (EMC) suggested that SVC was just a [bump in the wire] which could not possibly improve performance of existing disk arrays. IBM showed clients that putting cache(SVC) in front of other cache(back end devices) does indeed improve performance, in the same way that multi-core processors successfully use L1/L2/L3 cache. Now, EMC is claiming their cache-based VPLEX improves performance of back-end disk. My how EMC's story has changed!
So now, EMC announces VPLEX, which sports a blend of SVC-like and Invista-like characteristics. Based on blogs, tweets and publicly available materials I found on EMC's website, I have been able to determine the following comparison table. (Of course, VPLEX is not yet generally available, so what is eventually delivered may differ.)
Scalable, 1 to 4 node-pairs
One size fits all, single pair of CPCs
SVC-like, 1 to 4 director-pairs
Works with any SAN switches or directors
Required special "smart" switches (vendor lock-in)
SVC-like, works with any SAN switches or directors
Broad selection of IBM Subsystem Device Driver (SDD) offered at no additional charge, as well as OS-native drivers Windows MPIO, AIX MPIO, Solaris MPxIO, HP-UX PV-Links, VMware MPP, Linux DM-MP, and comercial third-party driver Symantec DMP.
Limited selection, with focus on priced PowerPath driver
Invista-like, PowerPath and Windows MPIO
Read cache, and choice of fast-write or write-through cache, offering the ability to improve performance.
No cache, Split-Path architecture cracked open Fibre Channel packets in flight, delayed every IO by 20 nanoseconds, and redirected modified packets to the appropriate physical device.
SVC-like, Read and write-through cache, offering the ability to improve performance.
Space-Efficient Point-in-Time copies
SVC FlashCopy supports up to 256 space-efficient targets, copies of copies, read-only or writeable, and incremental persistent pairs.
Like Invista, No
Remote distance mirror
Choice of SVC Metro Mirror (synchronous up to 300km) and Global Mirror (asynchronous), or use the functionality of the back-end storage arrays
No native support, use functionality of back-end storage arrays, or purchase separate product called EMC RecoverPoint to cover this lack of functionality
Limited synchronous remote-distance mirror within VPLEX (up to 100km only), no native asynchronous support, use functionality of back-end storage arrays
Provides thin provisioning to devices that don't offer this natively
Like Invista, No
SVC Split-Cluster allows concurrent read/write access of data to be accessed from hosts at two different locations several miles apart
I don't think so
PLEX-Metro, similar in concept but implemented differently
Non-disruptive tech refresh
Can upgrade or replace storage arrays, SAN switches, and even the SVC nodes software AND hardware themselves, non-disruptively
Tech refresh for storage arrays, but not for Invista CPCs
Tech refresh of back end devices, and upgrade of VPLEX software, non-disruptively. Not clear if VPLEX engines themselves can be upgraded non-disruptively like the SVC.
Heterogeneous Storage Support
Broad support of over 140 different storage models from all major vendors, including all CLARiiON, Symmetrix and VMAX from EMC, and storage from many smaller startups you may not have heard of
Invista-like. VPLEX claims to support a variety of arrays from a variety of vendors, but as far as I can find, only DS8000 supported from the list of IBM devices. Fellow blogger Barry Burke (EMC) suggests [putting SVC between VPLEX and third party storage devices] to get the heterogeneous coverage most companies demand.
Back-end storage requirement
Must define quorum disks on any IBM or non-IBM back end storage array. SVC can run entirely on non-IBM storage arrays
HP SVSP-like, requires at least one EMC storage array to hold metadata
SVC 2145-CF8 model supports up to four solid-state drives (SSD) per node that can treated as managed disk to store end-user data
Invista-like. VPLEX has an internal 30GB SSD, but this is used only for operating system and logs, not for end-user data.
In-band virtualization solutions from IBM and HDS dominate the market. Being able to migrate data from old devices to new ones non-disruptively turned out to be only the [tip of the iceberg] of benefits from storage virtualization. In today's highly virtualized server environment, being able to non-disruptively migrate data comes in handy all the time. SVC is one of the best storage solutions for VMware, Hyper-V, XEN and PowerVM environments. EMC watched and learned in the shadows, taking notes of what people like about the SVC, and decided to follow IBM's time-tested leadership to provide a similar offering.
EMC re-invented the wheel, and it is round. On a scale from Invista (zero) to SVC (ten), I give EMC's new VPLEX a six.
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.
Well, it's Wednesday, and you know what that means... IBM Announcements!
(Actually most IBM announcements are on Tuesdays, but IBM gave me extra time to recover from my trip to Europe!)
Today, IBM announced [IBM PureSystems], a new family of expert-integrated systems that combine storage, servers, networking, and software, based on IBM's decades of experience in the IT industry. You can register for the [Launch Event] today (April 11) at 2pm EDT, and download the companion "Integrated Expertise" event app for Apple, Android or Blackberry smartphones.
(If you are thinking, "Hey, wait a minute, hasn't this been done before?" you are not alone. Yes, IBM introduced the System/360 back in 1964, and the AS/400 back in 1988, so today's announcement is on scheduled for this 24-year cycle. Based on IBM's past success in this area, others have followed, most recently, Oracle, HP and Cisco.)
Initially, there are two offerings:
IBM PureFlex™ System
IBM PureFlex is like IaaS-in-a-box, allowing you to manage the system as a pool of virtual resources. It can be used for private cloud deployments, hybrid cloud deployments, or by service providers to offer public cloud solutions. IBM drinks its own champagne, and will have no problem integrating these into its [IBM SmartCloud] offerings.
To simplify ordering, the IBM PureFlex comes in three tee-shirt sizes: Express, Standard and Enterprise.
IBM PureFlex is based on a 10U-high, 19-inch wide, standard rack-mountable chassis that holds 14 bays, organized in a 7 by 2 matrix. Unlike BladeCenter where blades are inserted vertically, the IBM PureFlex nodes are horizontal. Some of the nodes take up a single bay (half-wide), but a few are full-wide, take up two bays, the full 19-inch width of the chassis. Compute and storage snap in the front, while power supplies, fans, and networking snap in the back. You can fit up to four chassis in a standard 42U rack.
Unlike competitive offerings, IBM does not limit you to x86 architectures. Both x86 and POWER-based compute nodes can be mixed into a single chassis. Out of the box, the IBM PureFlex supports four operating systems (AIX, IBM i, Linux and Windows), four server hypervisors (Hyper-V, Linux KVM, PowerVM, and VMware), and two storage hypervisors (SAN Volume Controller and Storwize V7000).
There are a variety of storage options for this. IBM will offer SSD and HDD inside the compute nodes themselves, direct-attached storage nodes, and an integrated version of the Storwize V7000 disk system. Of course, every IBM System Storage product is supported as external storage. Since Storwize V7000 and SAN Volume Controller support external virtualization, many non-IBM devices will be supported automatically as well.
Networking is also optimized, with options for 10Gb and 40Gb Ethernet/FCoE, 40Gb and 56Gb Infiniband, 8Gbps and 16Gbps Fibre Channel. Much of the networking traffic can be handled within the chassis, to minimize traffic on external switches and directors.
For management, IBM offers the Flex System Manager, that allows you to manage all the resources from a single pane of glass. The goal is to greatly simplify the IT lifecycle experience of procurement, installation, deployment and maintenance.
IBM PureApplication™ System
IBM PureApplication is like PaaS-in-a-box. Based on the IBM PureFlex infrastructure, the IBM PureApplication adds additional software layers focused on transactional web, business logic, and database workloads. Initially, it will offer two platforms: Linux platform based on x86 processors, Linux KVM and Red Hat Enterprise Linux (RHEL); and a UNIX platform based on POWER7 processors, PowerVM and AIX operating system. It will be offered in four tee-shirt sizes (small, medium, large and extra large).
In addition to having IBM's middleware like DB2 and WebSphere optimized for this platform, over 600 companies will announce this week that they will support and participate in the IBM PureSystems ecosystem as well. Already, there are 150 "Patterns of Expertise" ready to deploy from IBM PureSystem Centre, a kind of a "data center app store", borrowing an idea used today with smartphones.
By packaging applications in this manner, workloads can easily shift between private, hybrid and public clouds.
If you are unhappy with the inflexibility of your VCE Vblock, HP Integrity, or Oracle ExaLogic, talk to your local IBM Business Partner or Sales Representative. We might be able to buy your boat anchor off your hands, as part of an IBM PureSystems sale, with an attractive IBM Global Financing plan.
I gotten several emails expressing worry that I have fallen off the face of th earth. The last two weeks have been educational and eye-opening for me. I can't provide details in my blog, so I will just say that it involved government agencies that IBM refers to as "dark accounts", and that I am now back safely in the USA. Between adjusting to time zone differences, ridiculously long hours, and restricted access to the internet, I was unable to blog lately.
Instead, I will resume my coverage of the [IBM System Storage Technical University 2011]. The "Solutions Expo" runs Monday evening through Wednesday lunch. This is a chance for people to explore all the solutions that are part of IBM's large "eco-system" for IBM System storage and System x products. There were several sponsors for this event.
As is often the case at these conferences, the various booths hand out fun items. The hot items this year were tie-dyed tee-shirts from Qlogic, and propeller beanies from the IBM rack and power systems team. Here is Amanda, one of the bartenders showing off the latter.
After the expo on Tuesday night, my friends at [Texas Memory Systems] held an after-party. Unlike the pens, tee-shirts and keychains at the Expo, these guys had a raffle for real storage products. Here is Erik Eyberg handing out a RamSan PCIe card, valued at $14,000 or so. IBM recently certified the TMS RamSan as External SSD storage for the IBM SAN Volume Controller (SVC). The SVC can optimize performance using this for automated sub-LUN tiering with the IBM System Storage Easy Tier feature.
Well it's Tuesday again, and you know what that means... IBM announcements! Yesterday, at the IBM Edge conference here in Orlando, Florida, IBM announced its new apporach to storage, and a whole bunch of storage products, enhancements, and services. I will focus on some key ones here, and save the rest for next week.
IBM SAN Volume Controller (SVC) v6.4
The SVC is IBM's enterprise-class storage hypervisor. The latest software release, v6.4, can be installed on any SVC hardware, from the 2145-8F2 introduced back in 2005, to newer models like the 2145-CG8. Here are the key features:
Fibre Channel over Ethernet (FCoE) -- This is complete end-to-end support. For SVC units with 10GbE ports, these ports can be now be used for FCoE. This allows hosts to attach to SVC via FCoE, allows SVC node-to-node communication for clustering, and allows SVC to communicate to back-end devices via FCoE.
Real-Time Compression -- IBM ported over the patent Random Access Compression Engine (RACE) from the Real-Time Compression Appliances to SVC v6.4. This allows primary data, accessed via block-based protocols, to be compressed up to 80 percent. This feature is an extra priced feature by TB.
Non-Disruptive Volume move between I/O Groups -- If you don't already have SVC, you don't need to worry about this. For existing SVC customers, this allows volumes to be associated with two or more I/O groups, and that you can add or remove I/O groups non-disruptively. For example, if you want to move a volume from IOG1 to IOG2, then you add IOG2 to the list of I/O groups for the volume, let the multi-pathing software discover the additional paths, the remove IOG1, which then marks the previous IOG1 paths inactive. All this can be done while applications read and write data.
Dedicate FCP ports for Replication -- If you activate the two 10GbE Ethernet ports for FCoE, you can free up two FCP ports that you can dedicate for long-distance Metro Mirror or Global Mirror.
If you have SVC today, but are running an old release like v4.3 or v5.1, I recommennd you upgrade up to at least v6.2.05 release now. This release has been out for a year and is very stable, and serves as a great platform for a later upgrade to SVC v6.4.
IBM Storwize V7000 v6.4
The Storwize V7000 is IBM's midrange storage hypervisor. The latest software release, v6.4, can be installed on existing block-only Storwize V7000 units in the field. The Storwize V7000 v6.4 gets all the features listed above, as well as the following:
Four-way clustering -- Previously, you could cluster two Storwize V7000 controller enclosures together (4 canisters total). To cluster three or four controllers required an RPQ. Now, IBM supports up to four Storwize V7000 controller enclosures (8 canisters) without an RPQ.
Direct Fibre Channel attach -- A lot of people are using Storwize V7000 inside single-rack configurations, so it makes sense not to require a SAN switch for just a few Windows, Linux or VMware servers. An RPQ is now available to allow this to happen.
IBM Tivoli Storage Productivity Center (TPC) v5.1
TPC is already ranked one of the best Storage Infrastructure Management software in the market, and this release will just solidify its lead. Key features include:
Upward integration to higher level management systems
A new, intuitive, easy-to-use web-based GUI inspired by the XIV GUI
Integration of COGNOS to be able to generate and customize reports
Support for SONAS systems
There are several presentations on TPC this week that will go into more detail. Check out the [TPC Facebook page].
My latest book Inside System Storage: Volume IV is now available!
Yes, can you believe it? I have published my fourth volume in my "Inside System Storage" series! It is available in three formats:
Hardcover with dust jacket
eBook (Adobe Acrobat PDF)
You can order this, and all my other books, in all formats, directly from my [Author Spotlight] page. The paperback will also be available soon from other online booksellers, search for ISBN 978-1-105-72213-4.
IBM DS3500 Express
The DS3500 is our entry-level block-based device, designed specifically for random I/O workloads. This includes databases, email repositories, traditional business applications, and on-line transactional workloads. Here are the new features:
Dynamic Disk Pooling, similar to what XIV does to reduce disk rebuild times, but using a RAID-6 like approach per chunk of data.
Thin Provisioning using Dynamic Disk Pooling
Asynchronous Logical Unit Access (ALUA) failover
Enhanced FlashCopy, improved scalability, consistency groups and rollback support
VMware API for Array Integration (VAAI) support. This includes Write Same, Extended Copy, and Atomic Test & Set.
The DS3500 replaces the previous models of DS3200, DS3300 and DS3400 models.
The DCS3700 is our entry-level/midrange block-based device, replacing the DCS9900 model, designed specifically for sequential I/O workloads. This includes Big Data analytics, Hadoop, High Performance Computing (HPC), video surveillance, and television broadcasting. It holds 60 drives in a 4U controller enclosure.
Well, it's Tuesday, and you know what that means... IBM announcements!
In today's environment, clients expect more from their storage, and from their storage provider. The announcements span the gamut, from helping to use Business Analytics to analyze Big Data for trends, insights and patterns, to managing private, public and hybrid cloud environments, all with systems that are optimized for their particular workloads.
There are over a dozen different announcements, so I will split these up into separate posts. Here is part 1.
IBM Scale Out Network Attach Storage (SONAS) R1.3
I have covered [IBM SONAS] for quite some time now. Based on IBM's General Parallel File System (GPFS), this integrated system combines servers, storage and software into a fully functional scale-out NAS solution that support NFS, CIFS, FTP/SFTP, HTTP/HTTPS, and SCP protocols. IBM continues its technical leadership in the scale-out NAS marketplace with new hardware and software features.
The hardware adds new disk options, with 900GB SAS 15K RPM drives, and 3TB NL-SAS 7200 RPM drives. These come in 4U drawers of 60 drives each, six ranks of ten drives each. So, with the high-performance SAS drives that would be about 43TB usable capacity per drawer, and with the high-capacity NL-SAS drives about 144TB usable. You can have any mix of high-performance drawers and high-capacity drawers, up to 7200 drives, for a maximum usable capacity of 17PB usable (21PB for those who prefer it raw). This makes it the largest commercial scale-out NAS in the industry. This capacity can be made into one big file system, or divided up to 256 smaller file systems.
In addition to snapshots of each file system, you can divide the file system up into smaller tree branches and snapshot these independently as well. The tree branches are called fileset containers. Furthermore, you can now make writeable clones of individual files, which provides a space-efficient way to create copies for testing, training or whatever.
Performance is improved in many areas. The interface nodes now can support a second dual-port 10GbE, and replication performance is improved by 10x.
SONAS supports access-based enumeration, which means that if there are 100 different subdirectories, but you only have authority to access five of them, then that's all you see, those five directories. You don't even know the other 95 directories exist.
I saved the coolest feature for last, it is called Active Cloud Engine™ that offers both local and global file management. Locally, Active Cloud Engine placement rules to decide what type of disk a new file should be placed on. Management rules that will move the files from one disk type to another, or even migrates the data to tape or other externally-managed storage! A high-speed scan engine can rip through 10 million files per node, to identify files that need to be moved, backed up or expired.
Globally, Active Cloud Engine makes the global namespace truly global, allowing the file system to span multiple geographic locations. Built-in intelligence moves individual files to where they are closest to the users that use them most. This includes an intelligent push-over-WAN write cache, on-demand pull-from-WAN cache for reads, and will even pre-fetch subsets of files.
No other scale-out NAS solution from any other storage vendor offers this amazing and awesome capability!
IBM® Storwize® V7000
Last year, we introduced the [IBM Storwize V7000], a midrange disk system with block-level access via FCP and iSCSI protocols. The 2U-high control enclosure held two cannister nodes, a 12-drive or 24-drive bay, and a pair of power-supply/battery UPS modules. The controller could attach up to nine expansion enclosures for more capacity, as well as virtualize other storage systems. This has been one of our most successful products ever, selling over 100PB in the past 12 months to over 2,500 delighted customers.
The 12-drive enclosure now supports both 2TB and 3TB NL-SAS drives. The 24-drive enclosures support 200/300/400GB Solid-State Drives (SSD), 146 and 300GB 15K RPM drives, 300/450/600GB 10K RPM drives, and a new 1TB NL-SAS drive option. For those who want to set up "Flash-and-Stash" in a single 2U drawer, now you can combine SSD and NL-SAS in the 24-drive enclosure! This is the perfect platform for IBM's Easy Tier sub-LUN automated tiering. IBM's Easy Tier is substantially more powerful and easier to use than EMC's FAST-VP or HDS's Dynamic Tiering.
Last week, at Oracle OpenWorld, there were various vendors hawking their DRAM/SSD-only disk systems, including my friends at Texas Memory Systems, Pure Storage, and Violin Memory Systems. When people came to the IBM booth to ask what IBM offers, I explained that both the IBM DS8000 and the Storwize V7000 can be outfitted in this manner. With the Storwize V7000, you can buy as much or little SSD as you like. You do not have to buy these drives in groups of 8 or 16 at a time.
The Storwize V7000 is the sister product of the IBM SAN Volume Controller, so you can replicate between one and the other. I see two use cases for this. First, you might have a SVC at a primary location, and decide to replicate just the subset of mission-critical production data to a remote location, and use the Storwize V7000 as the target device. Secondly, you could have three remote or branch offices (ROBO) that replicate to a centralized data center SAN Volume Controller.
Lastly, like the SVC, the Storwize V7000 now supports clustering so that you can now combine multiple control enclosures together to make a single system.
IBM® Storwize® V7000 Unified
Do you remember how IBM combined the best of SAN Volume Controller, XIV and DS8000 RAID into the Storwize V7000? Well, IBM did it again, combining the best of the Storwize V7000 with the common NAS software base developed for SONAS into the new "Storwize V7000 Unified".
You can upgrade your block-only Storwize V7000 into a file-and-block "Storwize V7000 Unified" storage system. This is a 6U-high system, consisting of a pair of 2U-high file modules connected to a standard 2U-high control enclosure. Like the block-only version, the control enclosure can attach up to nine expansion enclosures, as well as all the same support to virtualize external disk systems. The file modules combine the management node, interface node and storage node functionality that SONAS R1.3 offers.
What exactly does that mean for you? In addition to FCP and iSCSI for block-level LUNs, you can carve out file systems that support NFS, CIFS, FTP/SFTP, HTTP/HTTPS, and SCP protocols. All the same support as SONAS for anti-virus checking, access-based enumeration, integrated TSM backup and HSM functionality to migrate data to tape, NDMP backup support for other backup software, and Active Cloud Engine's local file management are all included!
IBM SAN Volume Controller V6.3
The SAN Volume Controller [SVC] increases its stretched cluster to distances up to 300km. This is 3x further than EMC's VPLEX offering. This allows identical copies of data to be kept identical in both locations, and allows for Live Partition Mobility or VMware vMotion to move workloads seamlessly from one data center to another. Combining two data centers with an SVC stretch cluster is often referred to as "Data Center Federation".
The SVC also introduces a low-bandwidth option for Global Mirror. We actually borrowed this concept from our XIV disk system. Normally, SVC's Global Mirror will consume all the bandwidth it can to keep the destination copy of the data within a few seconds of currency behind the source copy. But do you always need to be that current? Can you afford the bandwidth requirements needed to keep up with that? If you answered "No!" to either of these, then the low-bandwidth option is you. Basically, a FlashCopy is done on the source copy, this copy is then sent over to the destination, and a FlashCopy is made of that. The process is then repeated on a scheduled basis, like every four hours. This greatly reduces the amount of bandwidth required, and for many workloads, having currency in hours, rather than seconds, is good enough.
I am very excited about all these announcements! It is a good time to be working for IBM, and look forward to sharing these exciting enhancements with clients at the Tucson EBC.
Well, I'm back safely from my tour of Asia. I am glad to report that Tokyo, Beijing and Kuala Lumpur are pretty much how I remember them from the last time I was there in each city. I have since been fighting jet lag by watching the last thirteen episodes of LOST season 6 and the series finale.
Recently, I have started seeing a lot of buzz on the term "Storage Federation". The concept is not new, but rather based on the work in database federation, first introduced in 1985 by [A federated architecture for information management] by Heimbigner and McLeod. For those not familiar with database federation, you can take several independent autonomous databases, and treat them as one big federated system. For example, this would allow you to issue a single query and get results across all the databases in the federated system. The advantage is that it is often easier to federate several disparate heterogeneous databases than to merge them into a single database. [IBM Infosphere Federation Server] is a market leader in this space, with the capability to federate DB2, Oracle and SQL Server databases.
Storage expansion: You want to increase the storage capacity of an existing storage system that cannot accommodate the total amount of capacity desired. Storage Federation allows you to add additional storage capacity by adding a whole new system.
Storage migration: You want to migrate from an aging storage system to a new one. Storage Federation allows the joining of the two systems and the evacuation from storage resources on the first onto the second and then the first system is removed.
Safe system upgrades: System upgrades can be problematic for a number of reasons. Storage Federation allows a system to be removed from the federation and be re-inserted again after the successful completion of the upgrade.
Load balancing: Similar to storage expansion, but on the performance axis, you might want to add additional storage systems to a Storage Federation in order to spread the workload across multiple systems.
Storage tiering: In a similar light, storage systems in a Storage Federation could have different capacity/performance ratios that you could use for tiering data. This is similar to the idea of dynamically re-striping data across the disk drives within a single storage system, such as with 3PAR's Dynamic Optimization software, but extends the concept to cross storage system boundaries.
To some extent, IBM SAN Volume Controller (SVC), XIV, Scale-Out NAS (SONAS), and Information Archive (IA) offer most, if not all, of these capabilities. EMC claims its VPLEX will be able to offer storage federation, but only with other VPLEX clusters, which brings up a good question. What about heterogenous storage federation? Before anyone accuses me of throwing stones at glass houses, let's take a look at each IBM solution:
IBM SAN Volume Controller
The IBM SAN Volume Controller has been doing storage federation since 2003. Not only can IBM SAN Volume Controller bring together storage from a variety of heterogenous storage, the SVC cluster itself can be a mix of different hardware models. You can have a 2145-8A4 node pair, 2145-8G4 node pair, and the new 2145-CF8 node pair, all combined together into a single SVC cluster. Upgrading SVC hardware nodes in an SVC cluster is always non-disruptive.
IBM XIV storage system
The IBM XIV has two kinds of independent modules. Data modules have processor, cache and 12 disks. Interface modules are data modules with additional processor, FC and Ethernet (iSCSI) adapters. Because these two modules play different roles in an XIV "colony", that number of each type is predetermined. Entry-level six-module systems have 2 interface and 4 data modules. Full 15-module systems have 6 interface and 9 data modules. Individual modules can be added or removed non-disruptively in an XIV.
IBM Scale-Out NAS
The SONAS is comprised of three kinds of nodes that work together in concert. A management node, one or more interface nodes, and two or more storage nodes. The storage nodes are paired to manage up to 240 nodes in a storage pod. Individual interface or data nodes can be added or removed non-disruptively in the SONAS. The underlying technology, the General Parallel File System, has been doing storage federation since 1996 for some of the largest top 500 supercomputers in the world.
IBM Information Archive (IA)
For the IA, there are 1, 2 or 3 nodes, which manages a set of collections. A collection can either be file-based using industry-standard NAS protocols, or object-based using the popular System Storage™ Archive Manager (SSAM) interface. Normally, you have as many collections as you have nodes, but nodes are powerful enough to manage two collections to provide N-1 availability. This allows a node to be removed, and a new node added into the IA "colony", in a non-disruptive manner.
Even in an ant colony, there are only a few types of ants, with typically one queen, several males, and lots of workers. But all the ants are red. You don't see colonies that mix between different species of ants. For databases, federation was a way to avoid the much harder task of merging databases from different platforms. For storage, I am surprised people have latched on to the term "federation", given our mixed results in the other "federations" we have formed, which I have conveniently (IMHO) ranked from least effective to most effective:
The Union of Soviet Socialist Republics (USSR)
My father used to say, "If the Soviet Union were in charge of the Sahara desert, they would run out of sand in 50 years." The [Soviet Union] actually lasted 68 years, from 1922 to 1991.
The United Nations (UN)
After the previous League of Nations failed, the UN was formed in 1945 to facilitate cooperation in international law, international security, economic development, social progress, human rights, and the achieving of world peace by stopping wars between countries, and to provide a platform for dialogue.
The European Union (EU)
With the collapse of the Greek economy, and the [rapid growth of debt] in the UK, Spain and France, there are concerns that the EU might not last past 2020.
The United States of America (USA)
My own country is a federation of states, each with its own government. California's financial crisis was compared to the one in Greece. My own state of Arizona is under boycott from other states because of its recent [immigration law]. However, I think the US has managed better than the EU because it has evolved over the past 200 years.
The Organization of the Petroleum Exporting Countries [OPEC]
Technically, OPEC is not a federation of cooperating countries, but rather a cartel of competing countries that have agreed on total industry output of oil to increase individual members' profits. Note that it was a non-OPEC company, BP, that could not "control their output" in what has now become the worst oil spill in US history. OPEC was formed in 1960, and is expected to collapse sometime around 2030 when the world's oil reserves run out. Matt Savinar has a nice article on [Life After the Oil Crash].
United Federation of Planets
The [Federation] fictitiously described in the Star Trek series appears to work well, an optimistic view of what federations could become if you let them evolve long enough.
Given the mixed results with "federation", I think I will avoid using the term for storage, and stick to the original term "scale-out architecture".