SAN TECHNOLOGY - finding the right gear
SAN TECHNOLOGY - finding the right
gear
From STORAGE Magazine
Vol 7, Issue 8 - November/December 2007
What critical factors do storage area networks - or SANs - offer to give
businesses that essential edge? Editor Brian Wall has been delving into its
deeper benefits
To stay competitive in the global marketplace, your people need to have
access to the right information, at the right time, in order to be effective,
creative and highly innovative. How can a storage area network (SAN) help your
business to achieve this?
Five years ago, the storage landscape in most organisations looked very
different," says Nick Broadbent, UK MD & EMEA operations, DataCore Software.
"Disparate islands of protected information floated in isolation within
departments. Back then, storage area networks were viewed as the domain of large
corporations with big budgets to support a Fibre Channel infrastructure and
backed by even bigger support and installation contracts."
Gradually, the movement has shifted towards SANs becoming affordable,
easy-to-use and available for all, allowing storage consolidation and thin
provisioning (automatically allocating storage to needy applications, just in
time) as a complete solution for all companies with any amount of data.
"This trend has flown against some of the roadmaps set in place by hardware
vendors, who have deliberately restricted the higher functions of SAN
technology, like thin provisioning, to work only with their own higher priced
storage arrays and disks," claims Broadbent. "It has been left to a few software
companies to pave the way and make SANs achievable and realistic by allowing for
both Fibre Channel and iSCSI environments, and making technology like thin
provisioning an open network-based service, as opposed to proprietary, that
works with all their existing storage hardware and supporting devices.
"So while, in essence, most organisations today understand that a SAN provides
the essential backbone and central repository, allowing all their business data
to be allocated, as required, across multiple business applications and
departments - with the overall result of reducing the amount of actual storage
required - there are some organisations that still demonstrate separate pockets
of information within key business applications that are not shared and not
therefore accessible to the whole business."
Indeed, he adds, this is sometimes done with intent outside of the SAN - eg, the
financial database may be stored as a dedicated storage appliance or
infrastructure that is isolated from other applications. "What we [at DataCore
Software] are seeing is that SANs give another boost to support remote offices
and those companies that fall into the 24x7 global small enterprise category."
For instance, DataCore has a typically sized SME (small to medium enterprise)
customer running around 10 servers in London, supporting a large online store
selling 100,000 products and remote offices in New York and Berlin. "Running a
SAN has allowed them to share more data remotely from these satellite offices
without clogging the corporate network with data, allowing them to share the
load across a dedicated storage infrastructure that can handle the peaks and
troughs a constantly globally trading infrastructure demands. And, when it comes
to staying competitive and TCO, most of our customers are able to re-utilise
existing hardware within the new SAN environment."
At the end of the day, says Broadbent, most companies now understand that
staying competitive when it comes to a storage infrastructure involves them
being empowered to eradicate inefficient, storage proliferation and allows re-utilisation
of existing investments.
Certainly during the past decade, SANs have become essential for companies
looking to increase storage utilisation and manageability, while reducing costs.
They allow applications to make far more efficient use of storage assets, with
improved data protection capabilities.
Historically, SANs have been, and continue to be, based on Fibre Channel (FC)
connectivity. This high-performance data centre technology has often been
unsuitable for remote offices and small-to-medium size environments. To address
these environments, SANs now also incorporate iSCSI as a method of
server/storage communication, solving multiple issues for large enterprises with
many remote offices and the IT requirements of SMEs.
"Both FC and iSCSI SANs offer a range of benefits over DAS," says John Rollason,
solutions marketing manager, NetApp, "such as improved backup and restore,
enhanced business continuity and simplified consolidation that address the needs
of today's data-intensive business. SAN solutions help provide the highest
productivity of people and the highest utilisation of assets."
The growth of business data continues to explode in the age of 24x7x365 internet
access, he adds. "Workers generate more email messages and file attachments;
users demand instant access to data like never before; IT managers install more
storage-hungry applications; and aging paper-based data continues to be
converted into digital form.
"However, with IT managers facing tighter budgets, the pressing challenge is to
do more with less, to squeeze the most data storage out of every IT pound. To
achieve this objective, they must start by assessing all data storage spending.
SAN virtualisation solutions are the real key to this. Typically, they not only
unify both FC SAN and IP SAN under a common architecture, but also virtualise
the entire storage infrastructure. Organisations have seen their storage
infrastructure costs cut in half by the use of virtualised storage. The
associated power, footprint and cooling savings are also an increasingly
important benefit." With a virtualised SAN solution such as this, adds Rollason,
you can transform existing heterogeneous multi-vendor storage systems into a
single storage pool.
"This simplifies storage provisioning and management, dramatically lowers backup
time, space and cost, increases storage utilisation (even more so with thin
provisioning, non-duplication and deduplication technologies) and results
in a dramatic reduction in total cost of ownership."
One major technical benefit of using a SAN is that all of an organisation's
information can be stored within one central point in the network. "This means
that it is simpler to manage the amount of data that the business accumulates
over time," states Paul Sudlow, systems engineering director, EMEA for
EqualLogic. "But, more importantly, it is easier to create and support other IT
strategies as well. An example of this includes disaster recovery and business
continuity planning. Because all the required critical data is in one place, it
is easier to back up and restore in the event of a failure.
"Beyond storage consolidation and data protection, SANs represent a good
opportunity for organisations to be more efficient in how they support all IT
operations through data centre virtualisation. Storage virtualisation within the
SAN brings a host of benefits to the business, including ease of use through
simplifying and automating complex operations," he adds.
Furthermore, by linking storage and server virtualisation together,
organisations can create a more fluid IT infrastructure and assign resources
more efficiently than using separate physical servers with direct attached
storage (DAS). This approach means that organisations can provide the most
appropriate data centre resources to users efficiently and economically.
"By centralising data into a virtual pool of storage in a SAN, IT managers are
allowed much more flexibility in resource management," comments Sudlow. "A
sophisticated form of storage resource management enabled by virtualisation is
thin provisioning, which allows users to present more storage resources to
applications than is currently physically present. By doing this, the company
can add storage at the rate that it is actually required, rather than all at
once. As a technology feature, thin provisioning allows users to reduce ongoing
costs from wasted power and cooling, while building on existing storage
investment."
While SANs provide centralised storage with associated benefits, the management
of that SAN must be considered, in order to deliver on the promises of ROI and
lower TCO. Companies should look to automate storage management wherever
possible to achieve results, argues Sudlow. It will also help staff concentrate
on more high-value activities to support the business.
Among the many challenges that organisations are now struggling to deal with are
the opposing demands being placed on them, which are becoming increasingly hard
to juggle.
"The business wants new applications rolled out in days, not weeks or months,"
says Peter Nicholls, manager of Cisco's UK & Ireland data centre solutions
specialist team. "Most of your budget is consumed running what's already there;
access to affordable power and cooling isn't keeping up with growth projections
and, what's more, you need to solve all this while cutting spending, meeting
corporate compliance and green objectives."
IT is now considered on a par with the airline industry, in terms of its carbon
footprint, Nicholls points out. "So, to meet these challenges, we must be
prepared to fundamentally rethink how we deploy technology. This is not
something that can be solved overnight and implementing an advanced SAN is not
going to provide an easy answer to all this. But it is a key piece of the puzzle
in delivering an agile infrastructure, aligned to the business."
SANs add a feature-rich, heterogen-eous abstract layer between a storage
subsystem and the servers and applications they support. This gives flexibility
in connectivity options within and between sites: options for backup recovery
and archiving; and tiered storage for cost-efficient access to critical data.
"Advanced SANs can add embedded services such as Network Assisted Serverless
Backup, serverless encryption and data mobility for migration/consolidation
between storage systems, with little or no downtime."
The greatest single advantage of implementing an advanced SAN is that
virtualisation provides a consolidating infrastructure, while maintaining the
separation that existing storage systems and networks were built to deliver. For
example, Cisco has saved more than US$50 million through storage virtualisation
alone.
"We also shut down over 5,000 servers through virtualisation and are saving even
more by embedding key virtualised services into the network," adds Nicholls.
"The efficiency and flexibility of storage virtualisation is too great to
ignore. Yet, we must not lose sight of where this fits, in context to the
overall architecture that will take us through the next five years of technical
and organisational change." ST
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