SAN Design: March 29, 2001 3:18 pm
53-0001575-01 BROCADE Technical Note Page: 20 of 31
2.9.1 SUMMARY
A variety of SAN designs topologies and port counts can be deployed today using Brocade switch. The Fabric Operating System provides
for auto-discovery and configuration of the SAN as devices are added and new switches included in an existing SAN. The user should
understand his environment, the components in the SAN, the relationship between hosts and storage, usage patterns and his needs for reli-
ability and redundancy when building a SAN. Information in this section can be used as guidance in choosing a design. The safe limits for
reliable SAN sizes supported as of this publication date are shown the Table 1 below.
NOTE:FOS release information. These versions of FOS are the recommended versions to use when targeting fabrics of the
size defined in this table. Later releases should work as well as denoted by the (+) symbol. The 2.2 Tree contains additional
licensed features not found in the 2.1 Tree of releases, however, in terms of compatibility and bug fixes the 2.1.9g and the
2.2.2 version are equivalent.
FIGURE 16. SAN Topologies and Port Counts Supported by Brocade
Fabric Type Switch
Count
FOS
Version
See Note
Port Count
Maximum ISL Comments
Meshed 16 2.1.9g+
2.2.2+
220 Single Port count max is with single ISL links in the mesh. Lower port counts if multiple ISL
links are used.
Star 18-20 2.1.9g+
2.2.2+
224 One to each core
from edge
switch
Fewer switches can be used and the SAN can be expanded as to maximum configura-
tion as more devices are added. Can still take advantage of locality if that is
known.however SAN allows for equal cost paths from any initiator to target.
Three Tier 20-24 2.1.9g+
2.2.2+
192-262 2 or more Figure 10 design: 190 host ports and 72 storage ports
Note: devices are not generally attached to the middle tier though it could be used for
device attach (add 12ports)