Temporary data set names

DFSMSdss must allocate the following temporary data sets to perform certain functions such as copy and restore. The high-level qualifiers of those data set names can be protected, and your installation must ensure that these temporary data sets can be allocated.

Message data set—

Allocated by DFSMSdss to store messages. This data set lets DFSMSdss print out messages by task rather than intermixing them. This data set is deleted when DFSMSdss completes the operation. System-generated temporary names are used.

Special DEFRAG or CONSOLIDATE data set—

Allocated by DFSMSdss to contain information about relocated DASD extents. The data set name is in the following format:

   SYS1.DFDSS.DEFRAG.xxxxxxxx.volser.DUMMY

where xxxxxxxx represents 8 bytes of X'FF', and volser is the volume serial number of the volume being defragmented. The data set is deleted when the DEFRAG or CONSOLIDATE operation ends successfully.

If the operation is interrupted (for example, if DFSMSdss is canceled), the data set is left on the volume. To delete the data set, repeat the DEFRAG or CONSOLIDATE operation. Before doing so, however, observe the following considerations:

Determine whether you need to convert the index VTOC (IXFORMAT) volume to a non-indexed VTOC (OSFORMAT) before rerunning the DEFRAG or CONSOLIDATE operation. Otherwise, the volume free space values might be incorrect.
Use the hexadecimal qualifier to prevent the deletion of this data.

Temporary copied data sets

Allocated by DFSMSdss when a copy is performed and deleted when the copy is completed.

The format of the temporary name depends on the number of qualifiers of the data set being copied:

Number of qualifiers (`n`)	Temporary name
1	`dsnhlq.Atidasid.chmmsstt`
2	First 2 qualifiers.`Atidasid.chmmsstt`
>2	First 3 qualifiers.`Atidasid.chmmsstt`

The next to last qualifier, Atidasid, is a combination of a fixed "A" character followed by a task id (tid) and an address space id (asid).

The last qualifier is chmmsstt where c is:

T: Target cluster name
D: Target data component name
I: Target index component name
U: Source cluster name
E: Source data component name
J: Source index component name
P: Source path name
Q: Target path name

and hmmsstt is the time stamp information in low-order hours digits (h), minutes (mm), seconds (ss), and hundredths of a second (tt).

Note: In the course of copying data sets, DFSMSdss renames the source data set using the above conventions. Whenever DFSMSdss renames a data set that is protected by RACF®, a component of the Security Server for z/OS®, to a temporary name a RACF profile must exist for the temporary data set name.

Temporary copied catalogs

Allocated by DFSMSdss when it copies a catalog. When DFSMSdss copies a catalog, two temporary data sets are used.

First, DFSMSdss allocates a temporary data set into which records are temporarily exported. The export data set name format is:

   CATHLQ.EXPORT.Thmmsstt

where,
CATHLQ

The first three high-level qualifiers of the catalog that is being copied.

hmmsstt

The time-stamp information in low-order hours digits (h), minutes (mm), seconds (ss), and hundredths of a second (tt).

Second, DFSMSdss allocates a temporary catalog. The temporary catalog name format is:

   CATHLQ.Thmmsstt

where,
CATHLQ

The first four high-level qualifiers of the catalog being copied.

hmmsstt

The time-stamp information in low-order hours digits (h), minutes (mm), seconds (ss), and hundredths of a second (tt).

Dummy data set—

Allocated by DFSMSdss when copying or restoring volumes and an indexed-VTOC needs rebuilding or the volume free-space values need recalculating. The data set name is in the following format:

   SYS1.VTOCIX.DSS.TEMP.volser

where volser is the volume serial number of the restored volume. Allocation of this data set is never successful because DFSMSdss uses dummy allocation values.