STORAGE: A sane justification

In an effort to continue to improve business productivity and customer

service, most organizations are deploying data intensive enterprise applications

like customer relationship management (CRM), enterprise resource planning (ERP),

and e-mail. This has resulted in an explosion of information and data that has

become the lifeblood of these organizations, greatly elevating the importance of

a sound storage strategy. Selecting a unified architecture that integrates the

appropriate technologies to meet user requirements across a range of

applications is central to ensuring storage support for mission critical

applications. Matching technologies to user demands allows for an optimized

storage architecture, providing the best use of capital and IT resources.

Storage area networks (SAN) have emerged as the best solution for advanced

storage requirements. Often, SANs can alleviate many if not all of the pain

points of IT managers, since they allow for more manageable, scalable, and

efficient deployment of mission-critical data. Not only do SANs provide advanced

functionality, but they also lower an organization's total cost of ownership (TCO)

and provide significant positive return on investment (RoI) versus a direct

attached storage (DAS) environment.

Not all SAN technologies are the same. However, in order to realize the

positive benefits of SAN deployment, the choice of vendor and SAN implementation

partner is just as critical as the SAN equipment itself. Centralized, efficient

management, intelligent SAN services, a truly robust and flexible platform and

global, 24x7 service and support are requisites for next-generation SAN

technologies. Any solution that closes off heterogeneous options-whether it is

protocol-, vendor-, or equipment-specific-will only be a transient solution

with limited strategic and RoI justification. The optimal SAN solution will have

a robust, high-performance architecture that creates new opportunities and

alternatives while protecting resource investments from unexpected turns in the

economic environment and changes in market adoption of new technology.

An IT Manager's Dilemma



IT managers across three states in the US identified the following five

major 'pain points' when asked about their storage management.

- Difficulty of managing large, disparate

islands of storage from multiple physical and virtual locations.



- Complexity of maintaining scheduled backups for multiple

systems and difficulty in preparing for unscheduled system outages.



- Inability to share storage resources and achieve efficient

levels of subsystem utilization.



- Shortage of qualified storage professionals to manage storage

resources effectively.



- Confusion over the justification of a plethora of storage

technology alternatives, including appropriate deployment of fiber channel,

Internet small computer systems interface (iSCSI), fibre channel over IP (FCIP),

and InfiniBand. To add to these technical dilemmas, IT managers are facing

restricted budgets and increasing costs of deploying and maintaining both DAS

and SANs, despite decreasing prices for physical storage in terms of average

street price (ASP) per terabyte. The result, that IT projects are faced with a

greater of scrutiny than ever before.

However, regardless of the economic environment and the

abundance of new technologies, organizations must continue to invest in IT

projects that support specific business goals and that can produce quick RoIs. A

well-planned, well-justified storage strategy will allow a business to emerge

from adverse market conditions in a better position to take advantage of new

opportunities. In effect, the choice of storage investment can actually result

in a sustainable competitive advantage versus the competition. For example, a

brokerage firm that loses the ability to commit transactions during trading

hours will suffer significant losses relative to a competitor.

A large consumer goods retailer that can't determine its

inventory in real time because of insufficient storage will suffer higher costs

than a competitor that has implemented storage provisioning and management tools

that can track inventory flows and store all relevant data in an easy-to-access

database.

It is important, therefore, that the decision makers in the

storage strategy include not only technical IT managers, but also business and

financial managers who want a greater strategic and financial justification in

order to invest the organization's capital.

Evolution and Benefits of Networked Storage



The evolution of SAN has progressed to the point where all organizations

should seriously evaluate their role in the future of their storage environment.

According to a recent report from Gartner Dataquest, the market for SAN-attached

external storage in 2005 will exceed $22 billion, representing almost three

million terabytes of data.

The main reason SANs have emerged as the leading advanced

storage option is because they often can alleviate many if not all of the pain

points of IT managers. They allow for more manageable, scalable, and efficient

deployment of mission-critical data.

A large number of enterprises have already tested or

implemented production SANs and many industry analysts have researched the

actual benefits of these implementations. A study of large enterprise data

center managers by Gartner andWitSoundview shows that 64 percent of those

surveyed were either running or deploying SANs. Another study by the Aberdeen

Group cites that nearly 60 percent of organizations that have a SAN installed

have two or more separate SANs. The study also states that 80 percent of those

surveyed felt that they had satisfactorily achieved their main goals for

implementing a SAN. Across the board, all vendor case studies and all industry

analyst investigations have found the following benefits of SAN implementation

when compared to a DAS environment: ease of management, increased sub-system

utilization, reduction in backup expense, and lower TCO.

Business Impact of Current SANs



IT managers perceive the benefits of a centralized point of management since

it makes the everyday work of storage administrators easier. But, to truly

justify a SAN investment from both a technical and a business perspective, it is

necessary to attach concrete savings in money terms to the benefit or to define

a concrete source of competitive advantage. While the hard cost savings are

usually enough to justify migrating to a SAN, the less-easily quantifiable 'soft

benefits' may provide the most compelling argument.

A good IT investment (and, therefore, a good networked

storage architecture) should lead to a lower TCO and a higher RoI. In this

paper, TCO refers to the full cost of a project including upfront capital costs

and recurring costs over the period of the project (two years, three years,

etc.), and RoI is the average expected cash flow over the period of the project

divided by the initial investment outlay.

There are three major quantifiable savings associated with

SANs that lower TCO and result in a large positive RoI versus DAS environment:

reduced management costs, reduced sub-system costs, and reduced backup costs.

There are also two more strategic benefits of SANs that, though difficult to

quantify, may be even more important justifications for SAN implementation: high

availability and disaster recovery.

Management Costs



A study by McKinsey and Merrill Lynch shows that the TCO of SAN solutions

typically is less than half that of DAS solutions primarily because of huge

savings in management costs. The study found that SANs were able to lower the

budget for storage administrators from 47 percent of total cost to less than 10

percent.

The main reason for the cost savings is that SANs are easier

to manage than DAS because of the existence of a simplified, central point of

control for monitoring, backup, replication, and provisioning. This results in

an increased amount of TB of data that a single storage administrator can

manage. This frees up time for administrators to devote to more value-added

activities. This time saving results in slower staff growth and ultimately

decreases the required rate of hiring.

Sub-system Costs



SANs allow any-to-any access and connectivity between storage and servers.
Therefore, servers can be better matched with underutilized sub-systems and

overall capacity utilization can increase. This leads to savings on future

sub-system purchases as less disks need to be added each year. For example, in

DAS environments it is usually possible to achieve 50 percent capacity

utilization of usable data storage space. So, if an organization has 20 TB of

data to store, it will actually have to purchase 40 TB of disk. Current SANs can

increase utilization to about 70—85 percent. The same organization would only

need 24—29 TB of disk in this scenario. The difference in storage utilization

can add up quickly in a fast-growing organization.

Scalability



Compared to physically separated SANs, VSANs (virtual SANs) offer much

greater flexibility. Moving a device from one VSAN to another requires only

configuration at the port level, rather than a physical move. Compared to

zoning, VSANs provide a more complete mechanism for traffic isolation by

enforcing control of frames at every step along the way, rather than only at the

edge of the fabric.

This partitioning of fabric services greatly reduces network

instability by containing fabric reconfigurations and error conditions within an

individual VSAN. Should a fabric function such as fabric shortest path first (FSPF)

have a failure, the failure is contained to the VSAN and has no effect on the

rest of the switch. VSANs also provide the same isolation between individual

VSANs as would exist between physically separated SANs. Traffic cannot cross

VSAN boundaries and devices may not reside in more than one VSAN. This attribute

of VSANs is of great value in service provider environments where absolute

separation must be maintained between customers. Since VSANs each run separate

instances of fabric services, each VSAN has its own zone server, name server,

and FSPF and can be zoned in exactly the same way in which SANs without VSAN

capability are zoned.

VSANs save customers money by enabling them to consolidate

physically separate switch infrastructures that may not have optimal port

utilization into one physical infrastructure that can be managed as a single

logical entity. Not only is this one infrastructure easier to manage, but in

general it will have fewer ports.

Excerpted from a Cisco white paper