HP XP20000/XP24000 HP StorageWorks XP Disk Array Mainframe Host Attachment and - Page 13

NOTE: For optimum performance, use a cable shorter than 103 km (64 mi). An ESCON host channel can connect to more than one storage unit port through an ESCON director. The S/390 or zSeries host system attaches to one port of an ESCON host adapter in the storage unit. Each storage unit adapter card has two ports. For the XP24000/XP20000 disk array, each ExSA has 4 ports per adapter card and 8 per pair. Cable lengths and types for ESCON adapters on zSeries hosts The cable that is attached to the host adapter can be up to 2 km (1.24 mi) in length using 50-μm fibre or 3 km (1.86 mi) in length for 62.5-μm fibre. This cable is used to make the connection between the following components: • Host channel controller v Peer controller host channel • Peer controller with appropriate equipment NOTE: Appropriate retention hardware to support cable attachments that control bend-radius limits comes with each ESCON host attachment. Logical paths and path groups for ESCON adapters on zSeries hosts Each ESCON adapter card supports two ESCON ports or links. Each port supports 64 logical paths. At the maximum of 32 ESCON ports, the number of logical paths is 2048. Each controller image supports up to 64 path groups. Each path group might have up to eight logical paths. Each controller image supports a maximum of 512 logical paths per control unit image. Data transfer for ESCON adapters on zSeries hosts The ESCON host adapter supports all data input buffer sizes up to 256 bytes. During write operations, the host adapter requests the minimum hexadecimal pacing count of X'02'. For commands whose parameter data length is not determined by the parameter data itself, the full transfer count in the command frame is requested in the first data request. The adapter supports an NDF-R count of 7 (that is, a maximum of eight data requests). Directors and channel extenders for ESCON adapters on zSeries hosts The storage system supports IBM ESCON directors 9032 Models 1, 2, 3, and 5. The storage system also supports IBM 9036 channel extenders to the distances that are allowed by the 9036 as described in "Cable lengths and types for ESCON adapters on zSeries hosts". The storage unit supports the 9729 Wavelength Division Multiplexer channel extender up to 50 km (31 mi). Identifying the port for TSO commands on zSeries hosts You can use the devserv command to identify ports on a zSeries or S/390 host. This command is used to identify the port ID for the MVS TSO commands for S/390 and zSeries hosts. Numbers such as 806, 804, 802, and 800 are internal microcode numbers. Numbers such as 00, 04, 08, and 0C XP Disk Array Mainframe Host Attachment and Operations Guide 13