HP StorageWorks XP Remote Web Console Software - Manual (Page 165)

Deleting Mode:
•
Normal: performs a normal release pair operation for the selected pair(s). The pair(s) will only
be released if the MCU is able to change the pair status of the M-VOL and R-VOL to Simplex.
•
All: allows you to release all TrueCopy for Mainframe Synchronous pairs with the same MCU
and RCU (same CU) as the selected pair. This option can be selected from the MCU or RCU.
This option releases the pairs more quickly than if you select all pairs on the TrueCopy for
Mainframe windows and release them.
•
Force: allows you to override the restrictions on releasing a TrueCopy for Mainframe pair. If
this option is selected, the pair(s) will be released even if the MCU is unable to communicate
with the RCU. This option may be used to free a host waiting for device-end from an MCU
which cannot communicate with its RCU, thus allowing host operations to continue. If this
option is not selected, the pair(s) will only be released if the MCU is able to change the pair
status of the M-VOL and R-VOL to Simplex. When the status of the pair(s) to be released is
Simplex or Deleting, the default setting is Force (cannot be changed). Otherwise, the default
setting is Normal.
Asynchronous Parameters:
•
Delete Range: The delete range option simplifies disaster recovery operations for TrueCopy
for Mainframe Asynchronous consistency groups at the RCU (secondary (remote) storage
system).
◦ C/T (RCU only): the RCU will release all TrueCopy for Mainframe Async pairs which have
the same consistency time.
◦ Volume (MCU or RCU): the MCU/RCU will release only the specified pair(s). This option
can be used to remove individual volumes from consistency groups.
For the Volume delete range setting, if you select pairs with duplex status and other than
duplex status in the same consistency group, unexpected suspend may occur during the
pair operations (suspend, resynchronize, release) under heavy I/O load conditions. You
can estimate whether the I/O load is heavy or not from the rate of sidefile cache (around
30%), or if you cannot see the sidefile cache rate, from the frequency of host I/O. The
release pair operations should be performed under light I/O load conditions.
◦ Group (MCU or RCU): all pairs in the same consistency group(s) as the selected pair(s)
will be released, regardless of pair status and consistency status. You must select only
one pair in each consistency group.
CAUTION: Do not use this option when releasing pairs at the RCU during disaster
recovery.
If you release the TrueCopy for Mainframe Asynchronous pair from the RCU with the
Group option, while the M-VOL continues accepting I/Os, the TrueCopy for Mainframe
Asynchronous pair is forcibly suspended. This suspend is due to R-VOL failure (not
user-requested). This status is temporary and will eventually change to Simplex. In this
case, it is possible that all pending recordsets are not settled.
The default delete range settings are:
◦ Two or more pairs in a group are selected: Volume.
◦ One pair is selected in each group and one or more M-VOLs are selected: Group.
◦ One pair is selected in each group and all selected volumes are R-VOLs: C/T.
When the Force Deleting Mode option is selected for an asynchronous pair, the Delete Range
option is set to Group to protect the integrity of the consistency group. This ensures that one or
more pairs in a consistency group cannot be forcibly deleted.
To release one or more TrueCopy for Mainframe pairs:
Releasing TrueCopy for Mainframe Pairs 165