.Part 1 Architecture HP SAN Design Reference Guide 785351-001

Table 3 (page 33) lists the data access performance ratings for each SAN fabric topology.

Table 3 Data access performance by SAN fabric topology

Data access performance

SAN topology DistributedCentralizedLocal

HighestHighestHighestSingle-switch fabric

Not recommendedNot recommendedHighestCascaded fabric

HighMediumMediumMeshed fabric

Not recommendedMediumHighestRing fabric

HighHighMedium

Core-edge fabric

(15:1, 7:1)

HighestHighestHigh

Core-edge fabric

(3:1, 1:1)

Topology maximums

Table 6 (page 34), Table 4 (page 33), and Table 5 (page 34) describe the maximum number of

supported switches and ports for specific fabric topologies. In some cases, the number may be

less than the maximums specified in the switch and fabric rules chapters. These differences relate

to the number of hops in the fabric topology, as well as the number of ISLs, which affects the

number of available user ports.

Consider the following:

• User ports are for server and storage connections.

• It is assumed that you have the minimum number of ISLs. If you require more ISLs, this reduces

the number of user ports available for server and storage connections. See the following

chapters for configuration limits:

◦ “B-series switches and fabric rules” (page 91)

◦ “C-series switches and fabric rules” (page 123)

◦ “H-series switches and fabric rules” (page 140)

• If you connect a Storage Management Appliance to the fabric, this further reduces the number

of ports available for server and storage connections.

B-series switches

Table 4 (page 33) lists the B-series switch and port maximums for specific fabric topologies.

Table 4 B-series switch and port topology maximums

Number of user portsTotal number of portsNumber of switchesSAN topology

5125121Single-switch fabric

2,300

2,560

Cascaded fabric

Meshed fabric

15Ring fabric

1,212

Ring fabric with satellite

switches

2,300Core-edge fabric

Topology maximums 33