Hitachi TrueCopy for IBM z/OS User and Reference Guide (T5211-96001, June 2007)

About TrueCopy for z/OS Operations 2-47
Hitachi Universal Storage Platform V TrueCopy for IBM z/OS User’s Guide
PPRC Support
All USP V with TCz installed support IBM PPRC host software functions. You
can perform most TCz operations by issuing PPRC TSO (or ICKDSF PPRCOPY)
commands from the host system console to the USP V. Using PPRC
commands, you can establish and delete remote copy communication paths;
establish, suspend, resynchronize, and release TCz Synchronous and TCzA
pairs/groups; and view TCz path and pair status. For operating systems that
do not support PPRC, the TCz software* is used to control and monitor TCz
operations. In this case, TCz provides only state-change-pending (SCP)
notifications with service information messages (SIMs).
Restrictions. If you plan to use PPRC commands instead of the TCz software
to perform TCz operations, the following restrictions apply:
• System option mode 114 (see Table 2-2) must be enabled to allow
automatic port configuration in response to PPRC commands. To fully support
an automated environment, the USP V is capable of automatically configuring
a fibre-channel port as an initiator or RCU target port if required in response
to the TSO CESTPATH and CDELPATH commands. However, even if you set
ON for system option mode 114, initiator ports will not automatically change
to RCU target ports, nor vice versa, when these ports are in initiator/external
mix mode. The USP V will make sure that the specified MCU port is offline to
the host, and will automatically configure it as an initiator port if required.
Similarly, the corresponding RCU port will also be configured as an RCU
target port if required. When the CDELPATH command is issued, the TCz
logical paths are removed, and if there are no more TCz or TC logical paths
on the port, the port is automatically changed from initiator port mode to
RCU target port mode.
Note: For fibre-channel interface, do not use the CESTPATH and CDELPATH
commands at the same time as the SCSI path definition function of LUN
Manager. The fibre-channel interface ports need to be configured as
initiator ports or RCU target ports before the CESTPATH and CDELPATH
commands are issued.
Caution: Before issuing the CESTPATH command, you must make sure
that the relevant paths are offline from the host(s) (e.g., configure the
Chipid offline, or deactivate the LPAR, or block the port in the ESCD). If
any active logical paths still exist, the add path operation will fail because
the port mode (RCU Target/Initiator) cannot be changed.
• The PPRC commands do not allow you to:
Change the RCU and CU options. The current default values are:
minimum paths = 1, RIO MIH time = 15 sec, incident of RCU = to any
host, PPRC support = yes, remote copy service SIM = not report, Freeze
option = disable. The TCz software* must be used to change these options.
Change the TCz async options. The current default values are: sidefile
threshold = 50%, offloading timer = 5 minutes. The TCz software* must be
used to change these options.