User`s guide

8 Implementing an Open IBM SAN
The FICON architecture prohibits this capability. The reason for the restriction is
because the base S/390 and zSeries I/O architecture uses a single byte for
addressing the I/O devices. This one-byte I/O address is not compatible with the
Fibre Channel, 3-byte port address. The FICON solution to this problem is to
disallow switch cascading.
1.3 IBM iSeries FC host system attachment
This topic describes the host system requirements and provides the procedure to
attach your IBM AS/400 or iSeries host system to the IBM Enterprise Storage
Server (ESS) with Fibre Channel adapters.
Your IBM AS/400 or iSeries host systems support the ESS as a peripheral
device.
The ESS presents individual 2105 LUNs to the AS/400 or iSeries host system.
You do not need to perform manual tasks to assign LUN addresses, as the ESS
will do it automatically during configuration.
1.3.1 Host limitations for the iSeries
In Table 1-2 we show a description of the LUN assignments for the iSeries host
system.
Table 1-2 iSeries host system limitations
The naming convention for the iSeries now describes models 270 and 8xx, which
attach through an FC adapter 2766. Use migration tower 5035 or 5077 for the
model 8xx. You can also make a connection using a 6501 with SCSI cables.
Note: The IBM AS/400 or iSeries host systems do not support serially
interconnected host systems attached to the ESS. They also do not support
serially interconnected ESS attachments to a single port on the host adapter.
Note: You cannot use the IBM Subsystem Device Driver on the AS/400 or
iSeries host system.
Host system LUN
assignments
per target
Configuration notes
iSeries (Fibre Channel) 0 - 32 There is one target per iSeries adapter