Simplifying the Tiers

DQI Bureau
New Update

Optimizing on storage environments is what every CIO wants to achieve. Many

enterprises are looking at ways and means of optimizing their storage assets;

while many have taken the virtualization route that is consolidation through

virtualization is an important first step towards realizing many of these

benefits. So, it becomes paramount in effectively configuring and managing the

virtualized tiered storage environments.


One of the most pressing issues facing organizations today is the need to

reduce storage costs. Simultaneously, single vendor management tools and

isolated pools of storage fragment the infrastructure, making it difficult to

share resources, improve operational efficiency. By implementing virtualized

tiered storage architecture, an IT organization can dramatically improve storage

capacities and lower capital and operational expenses. Virtualized tiered

storage better aligns data on storage systems by allowing users to efficiently

match storage attributes with the service level needs of individual business

applications. To achieve a seamless virtualized tiered storage environment, it

has to start from the design phase itself.

Configuring Tiered Storage

There are some key factors enterprises should consider while configuring,

managing and designing the tiered storage. When we look at design elements

oriented towards higher performance, the key things one should look at are

response time and throughput. The finer elements that need to be studied here

are aspects like I/O operations per second per gigabyte and megabyte capacity.

The second design element should factor in the critical two

parametersreliability and availability. So, the things to be studied here are

aspects like the extent of modular storage and whether its sufficient, and the

kind of RAID required. The major thing that needs to be considered is the

Logical Unit Number (LUN) and the kind of sizes required. The final design

element is the capacity management and the ability to scale the tier in the most

efficient manner.

The underlying design must facilitate certain key and critical storage

deliverables. First, such deliverable is the storage performance. As we look at

the individual parameters that impact the storage performance, a major downer

that ushers in inefficiencies comes from the storage being not tuned to the

demands. If the storage is not tuned to the demands it can dramatically erode

any benefits derived from virtualization. Storage needs to respond quickly to

increased workloads and overcome I/O bottlenecks automatically. But,

administrators do not have the time or resources to constantly tweak the

performance characteristics of their storage systems. As overall workloads

increase, storage systems need to scale easily without time consuming or costly



Meanwhile, another key area is managing disk capacity that has a direct

bearing on reliability and availability as well. For instance, managing the same

in virtualized environments can be time consuming, complex and costly. Many

companies over-provision the storage for virtual machines as a result, and

depend on machine templates to allocate space, hoping that one size will fit

all. Also, setting up storage that must host multiple virtual servers can

require significant configuration to achieve optimal performance. The point here

is I/O bottlenecks can kill virtual server applications.

The third important thing is whether your management approach enables you to

get the best solution at the most economical TCO. So, reducing capital and

operating costs is an essential benefit of virtualization. But, many companies

under-utilize their storage capacity and spend little time researching that how

fast their storage really is in their virtualized environments. Companies need

storage systems that are easy to expand, yet deliver the best possible

performance value.

The design elements must also usher in the much needed flexibility.

Virtualization deployment is growing. More applications are moving from

traditional, physical servers to a virtual pool of resources. Storage is no

different. Companies need storage systems that scale as the virtualization

demand grows, without sacrificing the savings that virtualization provides.

Storage systems as an integral component of virtualization infrastructures

should easily scale, preserve virtual resources and adapt to changing

conditions. As a bottomline, the key thing one needs to factor in the design of

a virtualized tiered storage system starts with the applications. It is the

business needs and applications that drive the storage requirements which guide

tier configuration. Most applications can benefit from a mix of storage service

levels using high performance where it is important, and less expensive storage

where it is not.


Points to Ponder

Operationally it is not efficient to configure unique tiers for each

application. Individually configuring a unique scheme for each application leads

to extra work, cost and provisioning delays. Instead, the recommended practice

is to develop a catalog of pre-defined tiers with pre-defined characteristics,

and then allocate storage to applications as needed. Minimum upgrade steps

should be defined for all storage tiers to make sure that the defined

performance levels can be guaranteed at any time. The minimum upgrade step

should include multiple RAID groups to allow distribution of the new LUNs across

multiple drives and array groups.

The ultimate goal for any CIO is to put in place a tiered architecture that

can consolidate heterogeneous storage solutions into single manageable pools. It

eliminates fragmentation of the storage environment caused by disconnected

islands of storage and interoperability problems, and creates stranded capacity

and duplicates storage networking equipments, contributing to escalating

hardware costs. Eliminating barriers to sharing, storage recovery and improving

capacity utilization rates can deliver sustainable long term savings by allowing

future purchase of storage assets to be deferred.

Meanwhile, with heterogeneous configurations the norm in enterprise data

centers, managing storage requires the use of many software tools from different

vendors. These tools frequently do not communicate well with each other,

complicating the process of provisioning, optimizing, moving and protecting

data, and increases the training costs. Hence, to avoid heterogeneous storage

management its a good idea to migrate to a universal storage platform that can

weed out the inherent storage pain areas.

Shrikanth G