Brocade FICON Administrator's Guide v7.1.0 (53-1002753-01, March 2013)
FICON Administrator’s Guide 7
53-1002753-01
FICON configurations
1
• The mainframes must be zSeries machines or System z processors: z196, z114, z800, 890,
900, 990, z9 BC, z9 EC, z10 BC, EC, and zEC12. Cascaded FICON requires 64-bit architecture
to support the 2-byte addressing scheme. Cascaded FICON is not supported on 9672 G5/G6
mainframes.
• z/OS version 1.4 or later, or z/OS version 1.3 with required PTFs/MCLs to support 2-byte link
addressing (DRV3g and MCL (J11206) or later) is required.
• Two-byte addressing, which has the following requirements:
- E_D_TOV must be the same on all switches in the fabric (typically this is not changed from
the default).
- R_A_TOV must be the same on all switches in the fabric (typically this is not changed from
the default).
- Insistent Domain ID.
- Fabric binding (strict SCC policy).
Qualified FICON cascaded configurations
Not all fibre channel fabrics are qualified for FICON. Cascaded FICON configurations are limited to
well-controlled paths. Only the channel paths described in this section are supported for FICON.
The 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.
Figure 4 and Figure 5 show two cascaded configurations. These configurations require Channel A
to be configured for 2-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 when extended fabric solutions are
deployed.
FIGURE 4 Cascaded configuration, two switches
Figure 5 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
Channel
A
Control
Unit
B
Switch
Domain ID = 21
Switch
Domain ID = 22
Channel
A
Control
Unit
C
Control
Unit
D
Switch
Domain ID = 23
Switch
Domain ID = 21
Switch
Domain ID = 22