Specifications

DATA CENTER BEST PRACTICES
SAN Design and Best Practices 7 of 84
This document does not consider physical environment factors such as power, cooling, and rack layout. Rather,
the focus is on network connectivity (both inter-switch and edge device) and software congurations.
Note: The scope of this document is switch-centric and does not discuss end-device setup, conguration, as well
as maintenance. Fabric monitoring, management, and diagnostics and McDATA and Brocade interoperability and
migration are covered in separate documents.
ARCHITECTING A SAN
The SAN planning process is similar to any type of project planning and includes the following phases:
•Phase I—Gathering requirements
•Phase II—Developing technical specications
•Phase III—Estimating project costs
•Phase IV—Analyzing Return on Investment (ROI) or Total Cost of Ownership (TCO) (if necessary)
•Phase V—Creating a detailed SAN design and implementation plan
When selecting which criteria to meet, you should engage users, server and storage Subject Matter Experts
(SMEs), and other relevant experts to understand the role of the fabric. Since most SANs tend to operate for
a long time before they are renewed, you should take future growth into account as SANs are difcult to re-
architect. Deploying new SANs or expanding existing ones to meet additional workloads in the fabrics requires
critical assessment of business and technology requirements. Proper focus on planning will ensure that the
SAN, once it is deployed, meets all current and future business objectives, including availability, deployment
simplicity, performance, future business growth, and cost. Tables in Appendix B are provided as a reference for
documenting assets and metrics for SAN projects.
A critical aspect for successful implementation that is often overlooked is the ongoing management of
the fabric. Identifying systems-level individual SMEs for all the components that make up the SAN, as well
as adequate and up-to-date training on those components, is critical for efcient design and operational
management of the fabric. When designing a new SAN or expanding an existing SAN, you should take into
account these parameters:
Application virtualization
•Which applications will run under a Virtual Machine (VM) environment?
•How many VMs per server?
•Migration of VMs under what conditions (business and non-business hours, need additional CPU or memory to
maintain response times)?
•Is there a need for SSDs to improve read response times?
Homogenous/heterogeneous server and storage platforms
•Do you use blade servers or rack servers?
•Is auto-tiering in place?
•Which Brocade Fabric OS® (FOS) runs in a multivendor environment?
•What is the refresh cycle of servers and storage platforms (2 years/3 years)?
Scalability
•How many user ports are needed now?
•How many Inter-Switch Links (ISLs)/Brocade UltraScale Inter-Chassis Links (ICLs) are required for
minimizing congestion?
•Do you scale-out at the edge or the core?