Specifications

DATA CENTER BEST PRACTICES
SAN Design and Best Practices 2 of 84
CONTENTS
INTRODUCTION .......................................................................................................................................... 6
Audience and Scope ............................................................................................................................ 6
Approach ............................................................................................................................................. 6
Overview ............................................................................................................................................. 6
ARCHITECTING A SAN ................................................................................................................................. 7
Operational Considerations ................................................................................................................... 8
Be the Pilot ......................................................................................................................................... 8
Diagnostics—Gen 5 Fibre Channel Platforms Only .................................................................................. 8
SAN DESIGN BASICS .................................................................................................................................. 9
Topologies ........................................................................................................................................... 9
Edge-Core Topology ...................................................................................................................... 10
Edge-Core-Edge Topology .............................................................................................................. 10
Full-Mesh Topology ....................................................................................................................... 10
Redundancy and Resiliency ................................................................................................................. 10
Switch Interconnections ..................................................................................................................... 11
ICL Connectivity for Brocade DCX and DCX 4-S Only........................................................................ 12
UltraScale ICL Connectivity for Brocade DCX 8510-8 and
DCX 8510-4 with Gen 5 Fibre Channel Only ................................................................................... 13
Brocade DCX 8510 UltraScale ICL Connection Best Practice ................................................................. 14
Mesh Topology .................................................................................................................................. 14
Device Placement .............................................................................................................................. 15
Trafc Locality.............................................................................................................................. 15
Fan-In Ratios and Oversubscription ............................................................................................... 17
DATA FLOW CONSIDERATIONS ................................................................................................................... 20
Congestion in the Fabric ..................................................................................................................... 20
Trafc versus Frame Congestion .......................................................................................................... 20
Sources of Congestion ................................................................................................................. 20
Mitigating Congestion .................................................................................................................. 21
Monitoring ................................................................................................................................... 21
Design Guidelines ........................................................................................................................ 22
AVAILABILITY AND HEALTH MONITORING .................................................................................................... 22
Health Monitoring .............................................................................................................................. 22
Brocade Fabric Watch ................................................................................................................... 22
Brocade Fabric Watch Recommendations ...................................................................................... 23
RAS Log ............................................................................................................................... 23
Audit Log .............................................................................................................................. 23
Brocade SAN Health .............................................................................................................. 23
Design Guidelines ................................................................................................................. 23
Monitoring and Notications ......................................................................................................... 24
Available Paths .................................................................................................................................. 24
McDATA Interop Mode .................................................................................................................. 24
Latencies .......................................................................................................................................... 25