Allocate a spare ACDS and
COMMDS when you allocate your originals.
Having spare copies eases the recovery process if SMS cannot access
the originals because of I/O errors. Place the spares on a device
that every system in your complex can access. Make certain that they
reside on a different device from your originals.
In order to
support 32 names, an SMS control data set is converted
from 8-name mode to 32-name mode. You must confirm this conversion,
using the operator console or ISMF.
Restrictions and Recommendations: - If an SMS system temporarily goes
down or has not
yet been started with SMS, then it is not part of the system-managed
storage environment. When you activate SMS on the system, it uses
the ACDS and COMMDS that are specified in its IGDSMSxx member. If
the COMMDS and ACDS are different from the ones used by the remainder
of the SMS complex, then the system runs as a separate SMS complex.
Consequently,
when you change the current ACDS or COMMDS, update the IGDSMSxx member
of SYS1.PARMLIB for each system in the SMS complex.
- Make
copies of your control data sets before the system mode is
converted for the following reasons:
- The conversion is permanent.
- You might
want to maintain them for coexistence with down-level
systems.
- There are special considerations to keep
in mind when you move
control data sets and their catalog entries. See z/OS DFSMS Managing Catalogs for
more information on special considerations, including the use of REPRO
MERGECAT.