Features - Enterprise Data Insights:
IBM BEGINS TO EXECUTE ON VIRTUALIZATION
by William Fellows for the451.com
IBM will deliver storage virtualization as a family of products under its
TotalStorage brand. The in-band SAN Volume Controller (aka Lodestone) is
expected this summer, and the StorageTank common file system is due by
year-end as the SAN File System. As a result of SAN Volume Controller's
arrival, IBM's OEM deal for DataCore's in-band appliance has been scrapped,
even though it originally claimed it wouldn't be.
We also believe IBM is working toward its own intelligent switch platform,
which will support a range of storage management applications -- similar to
Brocade's Silkworm application platform architecture -- including SAN Volume
Controller. Details are sketchy, and it's unclear whether IBM will leverage
partner technology or is going its own way. Also on the roadmap is a SAN
Integration Server, a prepackaged bundle of the Volume Controller with disk
and switch (expected at any time), and a CIM-based SAN Multiple Device Manager
that IBM will talk about later this year.
Impact assessment
The message
The first new component of IBM's TotalStorage Virtualization family is the
in-band SAN Volume Controller, due in the summer. StorageTank follows by
year-end as the SAN File System, while a prepackaged SAN Integration Server
(controller, switch and disk) and a multiple device manager are on the roadmap
as well.
Competitive landscape
When IBM gets into the game, everyone else gets nervous -- but the vast
majority of IBM's storage activity is still attached to its own systems.
DataCore is the initial casualty, losing its OEM deal. HP is juggling in-band
and out-of-band approaches. FalconStor and StoreAge continue with out-of-band
appliances. EMC claims virtualization is inherent in AutoIS. IBM's nascent
intelligent switch platform could be the curveball in an emerging market.
The451 assessment
After missteps, IBM has begun to execute on its comprehensive storage
virtualization strategy. The DataCore OEM deal is gone. It won't talk in
detail about an intelligent switch architecture we believe it is now working
on, a la Brocade's SilkWorm application platform. We suspect it's working
through the effect on its partner relationships before detailing plans.
Technology
IBM has been working on the in-band SAN Volume Controller for virtualizing
block data for three years now. It's been selling DataCore's SANsymphony
system in the meantime -- but no longer. That OEM deal is terminated, although
how many units IBM actually shipped is unclear: perhaps a hundred or so, and a
handful outside of the US.
IBM's Steve Legg, project lead on the controller product and a senior
architect in the storage software group out of Hursley, UK, says the
translation -- logical to physical mapping -- was the easy part of the system.
The difficulty was in creating redundancy and support elements (mirrored cache
writes, auto-restart, etc.). The software is up to 180,000 lines of C code
running on the Lite Blue embedded SuSe 8 Linux variant.
IBM admits that in-band appliances are in the way (they're in the data path)
and create latency. But it's only about 80ms, or an additional 1%, Legg says.
That's a small price to pay for not having to borrow MIPS from an application
server, as with out-of-band systems such as FalconStor, StoreAge or VersaStor.
And it also has its own cache. The software will be revved in future versions
for additional quality-of-service and copy functions. It currently supports
synchronous remote copy and mirroring, for disaster recovery, LAN-free backup
and nondisruptive replacement/migration. IBM is still debating whether to add
asynchronous support.
Because the system is deterministic in the resources it requires, IBM is
providing the hardware it's packaged in. It's unlikely to end up inside
third-party hardware anytime soon, but will feature in future blades and as
modules for the intelligent switch platform IBM is working on.
Each SAN Volume Controller contains two Lodestone nodes. The nodes are 1U,
two-processor xSeries servers with four 2GB/sec FC interfaces, 1GB/sec
throughput and 140,000 I/Ops. Nodes communicate in the package -- and with
other Lodestones on the storage network via a switch -- using a communications
mechanism called Paxos, instead of the less-reliable (and not IBM-owned)
TCP/IP. Paxos essentially keep the systems in sync.
SAN Volume Controller supports AIX, Windows, Solaris and HP-UX; Brocade,
McData and Inrange switches (Cisco in future); and IBM's own Fast and ESS
Shark arrays. It's committed to support at least a couple of third-party
environments (such as HDS and EMC) by the time it ships in volume.
Meanwhile, StorageTank, the out-of-band file aggregation/sharing common file
system, has already been heavily previewed. The trickiest part may be to
manage the synchronization of the host client with all versions of operating
system software being used. It will only be suitable for the very largest
customers that need to share data on a massive scale -- perhaps its top 100
customers, IBM acknowledges.
IBM is still debating how much of the application stack can move down onto
storage devices themselves. It's committed to doing it, but is examining how
and what. The group in Hursley is doing some interesting work moving DB2 tasks
such as filtering onto storage devices, although no product development
strategy has yet been decided. It's also working on a fiber channel RAID
controller for Shark.
The companion pieces to IBM's storage infrastructure software products (file
aggregation, block virtualization, multiple device management, replication)
are Tivoli's storage management applications.
Business Model
The key focus for SAN Volume Controller will be the midmarket, and there will
be a big push to get it sold through channel partners. It costs $60,000 and
up, which becomes viable in environments where an organization may be spending
$25,000 to back up each of five or six servers.
Why the midmarket? Because that's where all the bad disks are, IBM and its
partner Tectrade admit. It's where virtualization becomes a compelling
solution to a significant problem. It's also because in the first attempt at
SANs, IBM ignored this sector in favor of the high end and watched HP-Compaq
gain a market lead in the space. Tectrade maintains that storage
virtualization is entirely a marketing exercise this year and will become real
in 2004.
Three years ago, business partners accounted for less than 15% of IBM's
storage revenue. They're now bringing in over 50%. Still, IBM faces a
challenge to develop a truly 'open' storage business. The vast majority of
attachments (80+%) are to its own arrays.
Competition
IBM says HP's in-band CASA (nee StorageApps, nee SV3000) is fundamentally
handicapped by its reliance on using Windows as part of its stack. Other
in-band virtualization players include DataCore. Out-of-band mechanisms
include HP VersaStor, FalconStor and StoreAge.
Virtualization for virtualization's sake clearly isn't going to be a driver of
this market. Point product vendors are diversifying as fast as they can. IBM
wasn't first to market, but as its partner observes, most of what's happened
out there until now has been a marketing exercise. The opportunity is still
out there, and these early movements will be quickly forgotten.
Virtualization will be one component of highly modular storage management
architectures layered on 'intelligent' platforms that can support multiple
applications and protocols. While EMC has been at pains to point this out at
every opportunity, it's been less than forthcoming about the nature of
virtualization it will support in its AutoIS stack.
Courtesy www.the451.com
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