HP StorageWorks XP Disk Array Mainframe Host Attachment and Operations Guide XP24000, XP20000 (A5951 - 96151, September 2007)

NOTE:
* When the number of devices per CHL image is limited to a maximum of 1024, 16 CU images can be
assigned per CHL image. If one CU involves 256 devices, the maximum number of CUs per CHL image is
limited to 4.
Figure 1 Fibre Channel Device Addressing
FICON and ESCON considerations for zSeries hosts
This describes some things you should consider before you configure your system with FICON or
ESCON adapters for zSeries hosts.
Converting from ESCON to FICON
If the system requires x ESCON links, where x is the number of links to receive the performance and
availability attributes that you want, you must consider the number of FICON links that you need.
For example, you can map four ESCON links to a single FICON link and maintain approximately
equivalent performance. If the ESCON channel use is low, you can map six or eight ESCON links to
a single FICON link. If the ESCON channel use is high, you can map two ESCON links to a single
FICON link.
Multipathing for ESCON and FICON
Consider the difference between the path groups when you compare FICON to ESCON.
XP Disk Array Mainframe Host Attachment and Operations Guide 21