SAN Case Study (Instructor)

Business Profile:

A mid-sized publishing house has a centralized IT department located in San Francisco,

CA, connected to 3 branch offices on the west coast. Recent analysis of the storage

environment suggests that they are getting poor ROI in their storage infrastructure.

Current Situation/Issue:

The company’s current infrastructure consists of several storage arrays direct-attached to

a heterogeneous mix of 90 servers. All servers are dual-attached to the arrays for

reliability and redundancy.

Since each storage device has 32 connectivity ports, each could support a maximum of 16

servers. The company sees the 32-ports as a limitation. Each storage device has the disk

capacity to support more than 16 servers. However, there was no way to add a 17th

server to make use of that capacity and support future growth.

Proposal:

How would you suggest that the company restructure their environment? List the

advantages and disadvantages of your proposed solution. (Note: You will need to justify

your choice based on scalability, performance, and availability of the new solution.)

Solution: Connectivity should be the major point of this exercise.

Analyze the total port count required: 90 X 2 = 180.

This high port count rules out Fibre Channel Arbitrated Loop (FCAL) without

consideration of any storage ports. Fibre Channel Switched Fabric (FCSW) will be the

solution.

We recommend that the infrastructure be reconfigured as a mirrored Core/Edge topology.

• Advantages: Easy scalability, maximized storage utilization, and high availability via

mirrored topologies.

• Disadvantages: Possible performance hit.