Design Guidance

SAN Design: March 29, 2001 3:18 pm

2.7SAN BUILD ING BLOCK - MESHED FABR IC CON SISTIN G OF TWO STAR TOPOLOGIES CONNECTED BY A MESH

FIGURE 7. SAN Building Block showing expansion to 17 switch Mesh Fabric

SW		SW

SW				SW
SW				SW

•An atomic building block of 8 switches (star) for larger SANs

•Design can be expanded horizontally or vertically- horizontal expansion shown above using mesh design

•Redundant paths through the fabric by having at least two inter- switch links per switch

•Note: nodes can be on exterior switches or on interior switches. This will enable hosts/storage to be co-located on a switch if the application/data is closely associated with the host. Or, the interior switches can be used for storage devices shared by hosts on the exterior switches, eliminating a hop in the host<--->storage connection

•This basic 8 switch design with single ISL’s accommodates 104 end nodes

•When merging, connect the core switches using mesh

-Recommend use of FOS version 2.1.9g/2.2.2 or higher

-Do not exceed 17 switches in this topology

-No more than three inter-switch links per edge switch

-Maximum ports 220 (single ISL)

-Max hops 6

-Take advantage of any known locality

53-0001575-01

BROCADE Technical Note

Page: 12 of 31