Brocade FICON Administrator’s Guide (Supporting Fabric OS v7.3.0) - Manual (Page 19)

resulting fabric scenario after ISL failures must not result in an unsupported configuration. When
physical cabling is not practical to enforce these configurations, zoning or Traffic Isolation zoning (TI
zoning) with failover disabled may be used to ensure unsupported fabrics cannot be formed. Note that
these restrictions apply to logical switches and not the chassis.
The following figures show two cascaded configurations. These configurations require Channel A to be
configured for two-byte addressing and require IDID and fabric binding. It is recommended that there be
only two domains in a path from a FICON Channel interface to a FICON Control Unit interface. There
are exceptions to the two-domain rule in extended fabric configurations. Refer to
Extended fabric
configurations on page 17 for examples.
FIGURE 4 Cascaded configuration, two switches
The following figure illustrates multiple switches cascaded off of switch 21. As long as there is only one
hop from channel to control unit, the configuration is supported.
FIGURE 5 Cascaded configuration, core-edge architecture
Extended fabric configurations
Switches in cascaded configurations may be connected through interchassis links (ICLs), interswitch
links (ICLs), and FCIP. Connection using FCIP is through Fibre Channel extension devices, such as
7800 switches and FX8-24 blades. Following are example configurations.
For more information on long distance and extended fabrics, refer to the Fabric OS Administrator's
Guide. For more information on FCIP and extension products, refer to the Fabric OS FCIP
Administrator's Guide.
Extended fabric configurations
FICON Administrator's Guide 17
53-1003144-01