DLBL
assgn sys003 ign
dlbl test dummy (sys003 You must specify extent information
when you use the access method services control statements DEFINE SPACE, DEFINE DEFINE USERCATALOG, DEFINE CLUSTER (UNIQUE); or
when you use the IMPORT or IMPORTRA functions for a unique file.
When you enter the EXTENT option of the DLBL command, you are
prompted to enter the disk extents for the specified file. You must
enter extent information in accordance with the following rules: • You must specify the starting track number and number of tracks for
each extent, as follows:
This extent allocates 38 tracks, beginning with the 19th track, on a 3330 device. • All extents must begin and end on cylinder boundaries, regardless of
whetner the AMSERV file contains extent information in terms of
cylinders, tracks, or records. • Multiple extent entries may be entered
commas or on different lines. Commas
ignored.
on a single line separated by
at the end of a line are • Multiple extents for the same volume must be entered in numerically
ascending order; for example: 20 40 0, 600 80 These extents are valid for a 2314 device. • When you enter multivolume extents, you must specify the mode letter
and logical unit associated with each disk that contains extents; extents for each disk must be entered consecutively. For example:
assgn sy sOO 1 b
assgn sys002 c
assgn sys003 d
dlbl filel b (extent sys001 DMSDLB331R ENTER EXTENT SPECIFICATIONS: 100 60, 400 80, 60 40 d sys003 200 100 c svs002 400 100 c svs002 (null line)
specifies extents on disks accessed at modes B, C, and D. These
disks are assigned to the logical units SYS001, SYS002, and SYS003. Since B is the mode specified on the DLBL command line, it does not
need to be respecified along with the extent information. • A DASD volume must be mounted, accessed, and assigned for each disk
mode referenced in an extent.
When you are finished entering extent information, you must enter a
null line to terminate the DLBL command sequence. If you do not, an
error may result and you will have to reenter the DLBL command. If you
make any error entering the extents, you must reenter all the extent
information.
64 IBM VM/370 CMS Command and Macro Reference

DLBL
The OLBL command does not check the extents to see whether they are
on cylinder boundaries or whether they are entered in the proper
sequence. If you do not enter them correctly, the access method services
DEFINE function will terminate with an error. eMS assigns sequence numbers to the extents according to the order in
which they were entered. These sequence numbers are listed when you use
the LISTDS command with the EXTENT option.
In order to display the actual extents that were entered for a VSAM data set at DLBL definition time, the following commands may be entered:
DLBL (EXTENT) or QUERY DLBL EXTENT Either of these commands will provide the following information to
the user:
DDNAME The DOS filename or OS ddname. MODE The CMS disk mode identifying the disk on which the extent
resides. LOGUNIT The DOS logical unit specification (SYSxxx). This operand
will be blank for a data set defined while in CMS/OS environment; that is, the SET DOS ON command had not been
issued at DLBL definition time. EXTENT Specifies the relative starting track number and number of
tracks for each extent entered for the given dataset ddname.
If no DLBL definitions with extent information are active, the
following message is issued: DMSDLB324I NO USER DEFINED EXTENTS IN EFFECT EXTENTS: When you want to execute a program or use access method services to reference an existing multivolume VSAM data set, you must use the MULT option on the DLBL command that
identifies the file. When you use the MULT option, you are prompted to enter additional
disk mode letters, as follows:
assgn sys001 c
assgn sys002 d
assgn sys003 e
assgn sys004 f
assgn sys005 9 dlbl infile c {mult sys001 DMSDLB330R ENTER VOLUME SPECIFICATIONS: d sys002, e sys003 , f sys004 g sys005 (null line)
The above identifies a file that has extents on disks accessed at mo es
C, D, E, P, and G. These disks have been assigned to the logical un ts SYS001, SYS002, SYS003, SYS004, and SYS005. The rules for enter ng
multiple extents are: • All disks must be mounted, accessed, and assigned when you issue the
DLBL command. • You must not repeat the mode letter and logical unit of the disk that
js entered on the DLBL command line (C in the above example) . Section 2. eMS Commands 65