FW V06.XX/HAFM SW V08.02.00 HP StorageWorks SAN High Availability Planning Guide (AA-RS2DD-TE, July 2004)

Planning Considerations for Fibre Channel Topologies
126 SAN High Availability Planning Guide
— eServer zSeries 990 (z990) processor.
Note: FICON cascading is not supported for IBM S/390 Parallel Enterprise Servers
(Generation 5 or Generation 6).
■ The z/OS version 1.3 or version 1.4 operating system (with service as defined
in PSP Buckets for device type 2032, 2042, 2064, or 2066) must be installed
on the IBM server.
■ Licensed Internal Code (LIC) driver 3G at microcode level (MCL) J11206 or
later must be installed on the IBM server.
FICON Cascading Best Practices
A successful FICON-cascaded SAN environment requires a set of best practice
conventions as follows:
1. Connect fabric elements — Establish one or more ISLs between cascaded
directors of fabric switches as follows:
a. Ensure fabric elements are defined in the SAN management application.
If the elements must be defined, refer to the appropriate switch or director
installation manual for instructions.
b. Ensure the preferred domain ID for each director or switch is unique and
does not conflict with the ID of another fabric element.
c. Ensure the R_A_TOV and E_D_TOV values for fabric elements are
identical.
d. Route multimode or singlemode fiber-optic cables (depending on the type
of transceiver installed) between customer-specified E_Ports at each
fabric element.
2. Verify operation of local FICON applications — Ensure the ISL
connection(s) do not disrupt fabric element operation nor disrupt local FICON
(non-cascaded) traffic. Perform this step at each director or switch.
a. At the SAN management application’s physical map, right-click the
director or switch product icon, then select Element Manager from the
pop-up menu. The Element Manager application opens.