The class transition attributes allow you to specify:
- When a data set is eligible to transition
- Which copy technique to use to move the data set
- What action to take when there is a serialization error
There are three defined class transition attributes that can be
used to specify if and when data sets should transition:
- TIME SINCE CREATION indicates the YEARS, MONTHS and/or DAYS that
must elapse relative to the date that a data set was
created. If left blank (the default value), this indicates that no
transitions should occur based on these criteria.
- TIME SINCE LAST USE indicates the YEARS, MONTHS and/or DAYS that
must elapse relative to the date that a data set was
last referenced or used. If left blank (the default value), this
indicates that no transitions should occur based on these criteria.
- PERIODIC indicates a MONTHLY, QUARTERLY or YEARLY cycle for which
a data set should transition. If left blank (the default value), this
indicates that no transitions should occur based on these criteria.
TRANSITION COPY TECHNIQUE specifies whether a point in time copy
technique should be used. The available parameters are:
- STANDARD (STD)
- FAST REPLICATION PREFERRED (FRP)
- FAST REPLICATION REQUIRED (FRR)
- PRESERVE MIRROR PREFERRED (PMP)
- PRESERVE MIRROR REQUIRED (PMR)
These parameters function as follows:
- STANDARD (STD) specifies that only standard I/O should be used
to perform the data movement. This is the default.
- FAST REPLICATION PREFERRED (FRP) specifies that fast replication
should be used when possible. If fast replication cannot be used,
then it is acceptable to use standard I/O to perform the data movement.
- FAST REPLICATION REQUIRED (FRR) specifies that fast replication
is required. If fast replication cannot be used, then the transition
fails.
- PRESERVE MIRROR PREFERRED (PMP) specifies that a Metro Mirror
primary volume is allowed to become a FlashCopy target, and it would
be preferable that the Metro Mirror pair does not go into a duplex
pending state as a result of the FlashCopy operation when the target
volume is a Metro Mirror primary volume. If the preserve mirror operation
cannot be accomplished, then the FlashCopy operation is still to be
attempted. If the intended FlashCopy target volume is not a Metro Mirror primary volume, then the
rules for FAST REPLICATION PREFERRED (FRP) are followed.
- PRESERVE MIRROR REQUIRED (PMR) specifies that a Metro Mirror primary
volume is allowed to become a FlashCopy target, and the Metro Mirror
pair must not go into a duplex pending state as a result of the FlashCopy
operation when the target volume is a Metro Mirror primary volume.
If the preserve mirror operation cannot be accomplished, then the
FlashCopy should not be attempted. If the target volume is not a Metro Mirror primary volume, then the rules for FAST REPLICATION REQUIRED (FRR)
are followed.
SERIALIZATION ERROR EXIT specifies an action to take when the data
set cannot be exclusively serialized for the data movement. The available
parameters are:
These parameters function as follows:
- NONE specifies that the transition should fail with no additional
action. This is the default.
- DB2 specifies that DB2 should be invoked to close the data set.
If there are no DB2 transactions in progress and the data set is successfully
closed and unallocated, then the data set will be exclusively serialized.
If exclusive access is obtained, then the data set will be transitioned.
After the data set has moved, DB2 is reinvoked to allocate and open
the data set. If the serialization cannot be obtained or there are
active DB2 transactions then the transition will fail.
- CICS specifies that CICS should be invoked to
make the data set unavailable for use by CICS and to close all files
open to the data set. If these steps are successful, then the data
set will be exclusively serialized and then transitioned. After the
data set has moved, CICS is reinvoked to enable the CICS files to
use the data set and make available the data set to be used by CICS.
If the serialization cannot be obtained a second time, then the transition
will fail.
- ZFS specifies that zFS should be invoked to unmount the data set.
If the data set is successfully unmounted, then the data set will
be exclusively serialized. The unmount will fail if the file system
is currently accessing the data set. If exclusive access is obtained,
then the data set will be transitioned. After the data set has moved,
zFS is reinvoked to mount the data set.
- EXIT specifies that a user exit should be invoked to unserialize
the data set. The exit will be invoked twice: initially to unserialize
the data set, and a second time after the transition in order to reserialize
the data set. The transition will be performed if the data set can
be exclusively serialized after the user exit has been initially invoked.
Note: - When specifying a value other than NONE, ensure that only the
appropriate types of data sets are assigned to the management class.
For example, if DB2 is specified, then only DB2 objects should be
assigned to this management class.
- See z/OS DFSMSdss Storage Administration for more detailed information on the behavior of
this option.