Revolutionising - S3 – Part of Capita Plc

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storage

Revolutionising

storage management

The benefits of Software Defined Storage are clear to see,
but the journey along the road to being able to manage, for
example, 10s of Petabytes of data, needs careful planning.
DCSUK talks to Mark Smith, S3 Technical Director.

Q In general terms, what are the drivers behind the trend definition, software defined storage is where the software is separate
from the hardware it is managing. Of course the hardware may have
towards software-defined ‘everything’? some built in features such as automation or an abstraction layer but
the management software is a separate entity.
A  
There is a degree of hardware lock in that has always been Q  
resisted but for the most part software defined “everything” is more How does software defined storage compare to traditional
concerned with removing the barriers and simplifying management. SAN/NAS storage?
 
I don’t want to downplay the advances in hardware technology, in fact A  
without some of the memory and CPU developments we’d not be in a Traditional SAN and NAS products typically have their own,
position to run this advanced software on commodity hardware. what I would call, premium features. These could be replication,
When you look at the majority of storage vendors they are without a snapshots, tiering and management tools but they are usually specific
doubt accomplished software development houses. They do software to the product itself. All that so called “intelligence” costs money and
very well and typically outsource the hardware build or OEM existing not all customers need all the options. The systems themselves have
hardware. I doubt they want to fix power supplies or repair disk processor and memory resources to ensure they can deliver the
drives… storage services a customer might need regardless of whether they
are actually used. These systems are managed in groups, from the
Q   same manufacturer and can develop into silos of storage.
For how long has software defined storage existed, and is it  
a general storage networking industry trend, or only being Software defined storage takes most of the “intelligence” out of the
offered by certain vendors? traditional storage system and keeps it in the software that overlays
the storage components. It removes the silo problem in traditional
A   storage allowing storage to be grouped and classified in ways that
It depends on your interpretation of software defined. We’ve are much more relevant to your business. Eventually this will build
had storage virtualisation appliances for some time but when you look in to a catalog approach where the application owner requests more
under the covers of popular storage platforms you’ll notice a common storage resources and the software delivers the required space from
thread; commodity hardware with almost all of the intellectual property a predefined policy greatly simplifying the steps and tasks while
existing in the software. What we’ve been missing up until now has ensuring the resources are appropriate to the application. 
been the automation and policy driven approach to delivering storage
to the enterprise. Q  
What are the advantages/disadvantages of being able to use
Q   commodity hardware with software defined storage, as opposed
Is there a commonly accepted definition of software defined to the traditional customised storage/server hardware?
storage, or are there very different, but equally valid,
interpretations? A  
Most people hear commodity and think low cost but there
A   is much more to consider. Okay, low cost is a good start but if the
There are many different interpretations of software defined acquisition cost is low and the operating cost is high there is little
storage or SDS, especially from vendors who might stretch the
definition to be more applicable to their offering. In the true sense of a

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to be saved in the long term. A poorly conceived system can cause Q  
countless problems and understanding the requirements and How does software defined storage help with the Cloud/multi-
limitations is just as important in commodity hardware based solutions tenancy environment?
as it is in traditional storage systems.
  A  
I believe commodity hardware is just the start but we are going to see As a service provided it would seem to make perfect sense.
a shift to appliance based solutions where the commodity hardware If you want to offer self-service storage products to your customer
is replaced with a vendors own commodity hardware offering with the base then software defined storage is the first step. Don’t forget that
reassurance of quality and control. the cloud / multi-tenancy market is very aggressive with cost and
functionality being the key differentiators.
Q    
Software defined storage offers much in the way of agility? This goes back to the agility and scalability points already made. As a
service provider you would have the freedom to choose the most cost
A   correct commodity hardware and build a policy approach to delivering
Absolutely, agility and control are two major benefits to software the storage to the end user.
defined storage. If the intelligence is in the software and it’s built from  
the ground up as a software defined system then it should be able to
grow and shrink as the customer’s business dictates. As the whole Q  
point is the ability to use commodity hardware, the system should What about Big Data, does software defined storage have a
allow the customer to deploy new storage capacity from one vendor contribution to make here?
while retiring old storage from another.
A  
Q   To a degree but it depends on what the SDS vendor is offering.
Similarly, scalability is a major part of the software defined In a big data environment where we are managing petabytes, software
storage’s attraction? defined storage is one step on the road to the software defined
datacentre.
A    
Scalability and flexibility have combined into a new buzzword; With a true orchestration layer between IT services and the
elasticity. 6TB disk drives are here and this brings with it greater applications we can utilise different storage types for the correct
density than ever before. Performance with SSD devices has gone applications and even use a policy based catalog to determine the
through the roof too. Being able to use the latest and greatest compute and networking requirements and build a fully automated
technology where you need at a fraction of the traditional monolithic datacentre.
storage system costs is a big attraction.
  Q  
We can achieve compelling storage densities and efficiencies in Does software defined storage remove all of the intelligence
commodity based hardware but it means nothing without a reliable from the storage hardware?
software layer managing the feature set.
A  
Q   Not necessarily as there will always be specific technologies
As is reliability? that exist in hardware or productised software alone. We are likely to
see commodity hardware replace midrange and scale-out storage
A   systems in the long term but the Tier 0 and Tier 3 storage vendors
There is a perception that the convergence of products from always offer some type of enhanced technology embedded in their
different vendors will lead to complications and put reliability at risk. solutions that will remain.
Software defined storage relies on tight interoperability testing, well in
most cases. The lower cost hardware can enable a customer to build Q  
in more protection levels and create protection policies for specific Can you tell us a little bit about how virtualisation fits in the
data types without blowing the budget. software defined storage world – indeed, did it help to create it?

A  
Virtualisation could be considered the forerunner to all software
defined datacentre products. We’ve virtualised servers, we’ve
virtualised the networks so let’s virtualise the storage and put it all
together in a virtual datacentre and define it all in software so that
repetitive tasks can be automated and human error can be reduced.
Say hello to the future and the future is now.

Q  
Where do the virtual volumes, being offered by VMware for
example, fit in the software defined storage landscape?

A  
VMware virtual volumes rely on the VASA APIs to enable the
storage system to become aware of the virtual volumes and their
associations with the virtual machines. This visibility can only be a
good thing from a storage perspective and within a software defined
storage environment enables the correct management of the virtual
volumes.
 
To use these API enhancements previously you would need a storage
system that had been certified by VMware and that was on the
hardware compatibility list (HCL). With software defined storage we
only need to worry about the software layer. The theory is that any

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commodity storage hardware could benefit and we wouldn’t need to to choose what they want, when they want it. There will always be a
worry about the HCL provided the software stack was certified. market for traditional storage systems for those customers who are
too critical to embrace SDS or too small to afford it
Q  
Clustered file systems are also a part of software defined storage? Q  
Indeed, does the use of software defined storage guarantee an
A   open storage architecture, or are the hardware vendors
We should expect that all storage types should be part of the reluctant to give up their proprietary ‘edge’?
software defined storage ecosystem. Most of the well-known clustered
file systems are primarily software products first and foremost. Almost A  
all of the clustered file vendors uses commodity LINUX servers The cynic in me would say that you’ll be locked in anyway.
already, it’s the next logical step. Without doubt the storage hardware choices will broaden significantly. 
  If you are not locked into the hardware then you’ll be locked in to the
software but is it such a bad thing.
Q    
How does software defined storage work with the Fibre Channel The vendors that get criticised for “lock in” invest considerable funds
and iSCSI storage networking protocols? into research and development so they need to see a return. We want
to see the next great feature so we need to be on board to help fund
A   it. It doesn’t make it a bad thing.
That’s a bit of a red herring and a common question. The
protocols don’t change it’s where the features reside. If you need Q  
Fibre Channel and or iSCSI then that’s just fine. Fibre channel might And how is S3 helping its customers come to terms with the
impose some inflexibility in the physical layer but it’s not a show possibilities of software defined storage?
stopper
A  
Q   Well our view is to get close to the customer and understand
Software defined storage may well bring about significant what they are trying to achieve. You’d be amazed how many
IT automation, but it will never remove the need for humans to organisation do not have an accurate picture of what they actually
make those initial policy decisions? have today. S3 helps them understand where they are and listens to
where they want to be.
A    
We need to build the policies and understand the environment This is when the magic happens – our presales architects spring
before we can work on the automation. Like any new technology there into action and work out the best options to get to between the two.
is some upfront investment in time and resources but these should be If agility and elasticity are key business drivers then maybe the
paid back tenfold in future efficiencies. answer is SDS. We show our customers how the advances in
technology can benefit their business, save them valuable time
Even in well-established disaster recovery solutions they need a and reduce costs.
person to make the final decision to invoke the disaster recovery plan.
  Q  
I’m not sure mapping a LUN or resizing a volume is the most In conclusion, is software defined storage here to stay, or just
rewarding of tasks and with datacentre automation we can let those another step in the cyclical nature of the storage networking
administrators move on to something more fulfilling. industry, so the software will eventually go back in the box?!

Q   A  
Is it fair to suggest, therefore, that software defined storage can I’ve been the technical lead at S3 for over 20 years, we’ve seen
be ‘dangerous’ in the wrong hands? a lot of new technologies come and go.
 
A   Storage was direct attached to the server and then we centralised it
Just because its software doesn’t make it fool proof. We into disk arrays. Now we are going to break up the disk arrays and
are building a software defined storage system that has storage, distribute the data into storage servers.
connectivity and maintenance to consider – just as in the physical  
world. Architecture needs to be right and needs to cater for the Storage is no different to other IT resources, we are constantly
scalability and security the customer demands. Get it wrong at the thinking up new ways to make them better but the best doesn’t always
beginning and pay for it at the end. prevail. Without a doubt the benefits of software defined storage are
clear to see. Some of our customers are managing 10s of Petabytes,
Q   something that was impossible 10 years ago.
How do you see the storage hardware vendors adapting to life  
where their embedded/integral software offerings are being If we position it correctly and deliver it properly SDS will revolutionise
replaced by external, software defined storage solutions? the way we manage storage.

A  
We are seeing some of the storage vendors on the software
defined express train and making good progress. Hardware vendor
lock in will be a thing of the past with customers having the freedom

We are seeing some of the storage vendors on the software defined
express train and making good progress. Hardware vendor lock in will
be a thing of the past with customers having the freedom to choose

what they want, when they want it

26 www.dcsuk.info I September 2014