Specifications

DATA CENTER BEST PRACTICES
SAN Design and Best Practices 66 of 84
Together, the policy distribution and fabric-wide consistency settings provide a range of control on the security
policies from little or no control to very strict control.
For a detailed discussion of SAN security concepts and issues, see Securing Fibre Channel Fabrics, by Roger
Bouchard, on Brocade Bookshelf (www.brocade.com/bookshelf).
CAPACITY PLANNING
Gathering Requirements
The SAN project team should interview all stakeholders (IT application owners, nance, corporate facilities,
IT lab administrators, storage and network administrators, and end users) who have a vested interest in the
project—and this applies equally to planning for both new and updated SANs.
Application Owners
As critical stakeholders, application owners care because everyone is measured on application uptime.
Application outages are something that users notice, and they can have severe nancial impact for a business.
With a redundant or a resilient infrastructure, hardware outages are transparent to the user, and only SAN
administrators need to pay attention. Other questions to ask are as follows:
•What is the business goal for this application? (Is it a database that multiple applications rely on for business
transactions?)
•What are the availability requirements?
•Is the application latency sensitive?
•Are there peak periods of utilization or other trafc patterns?
•What are the IOPS requirements in terms of read/writes?
•What is the worst-case response time before an outage?
•Is the application running on a cluster?
•Has the application been benchmarked to determine the CPU and memory resources required?
•Is there application downtime that can be used for applying patches, software upgrades, and maintenance?
•Can the application run on a VM? If so, how many other VMs can co-exist on the same physical hardware?
The business criticality of the application will determine the SAN design and the DR strategy, including backup
and recovery. If the application is mission critical, the infrastructure must be fully redundant, with no single point
of failure for both mainframe or distributed open systems architectures.
Server and Storage Administrators
Once the application requirements have been dened, identify physical server and storage on which the
application and data will reside to determine the overall high-level architecture of the SAN, especially if this
includes existing equipment as well as new equipment.
•Gather information about the server(s) on which the applications are running (blade or rack, CPU, memory,
HBA/embedded FC switch, OS level, OS patch level, HBA driver version)?
•How many HBAs are in the rack servers?
•Does each server have single or multiple port HBAs?
•SDWhat is the primary storage for the application, and is there enough storage capacity to support this
application and data? What is the current cache utilization? Is there enough cache to meet required
response times?