Prerequisite
The enter files of MARENCP and MARENUCP must be adapted to permit the reservation file to be evaluated.
The following line has to be inserted in the procedure files for starting the MARENCP and MARENUCP tasks before the control program call, i.e. before the line /START-MARENCP or /START-MARENUCP respectively:
/ADD-FILE-LINK LINK-NAME=MARENLMF,FILE-NAME=<lmf_name>
<lmf_name> Name of the reservation file which is to be used.
If the reservation file is not stored under the SYSMAREN user ID, the complete path name has to be specified and the file must have the attribute SHARE=YES. Otherwise the file cannot be found by MARENCP (the message MARLM01 will be output and MARENCP will be terminated).
Evaluation procedure
When a free tape is requested, the entries in the reservation file are read sequentially.
For each entry the fields defined as comparison criteria are compared with the corresponding parameters of the tape request. Which fields are defined as comparison criteria is described below for the individual statements.
If a field contains blanks or *ANY, the comparison will be positive regardless of the value of the parameter.
As soon as an entry which matches all the comparison criteria is found, the following information is transferred from the entry to MARENCP and MARENUCP, where it is used for selecting the tape:
Location.
Number range.
Free-Pool-Name.
Reservation rejection.
The read operation is terminated. No further entries in the reservation file are checked.
If no entry is found which matches all the comparison criteria, the tape request is rejected.
MARENADM statement RESERVE-FREE-VOLUME
MARENCP evaluates the reservation file using the RESERVE-FREE-VOLUME statement of the MAREN or MARENADM utility routine.
Comparison criteria:
User ID.
File name.
Device type.
Location.
Start of number range.
End of number range.
Free-Pool-Name.
The comparison is negative in the following cases:
If the reservation file entry contains an “A2" in the “Utilization type (A/F)2" field or the name of a directory.
If the reservation file entry contains a value other than “*NO” in the “Free-Pool-Name” field.
HSMS/ARCHIVE statements
MARENCP evaluates the reservation file using the HSMS/ARCHIVE statements for tapes in the directory pool as well as the action statements requesting free tapes (save, archival, migration, export).
Comparison criteria:
User ID.
Directory.
Device type.
Start of number range.
End of number range.
Jobname.
SECURE-RESOURCE-ALLOCATION command
The SECURE-RESOURCE-ALLOCATION command reserves system resources such as tapes and/or tape devices. MARENUCP evaluates the reservation file when this is done.
Comparison criteria:
File name.
User ID.
Jobname.
Device type.
If the reservation file entry contains a directory, the comparison is negative.
Scratch request
If a scratch request is received (i.e. a tape is requested but no archive number is specified), MARENUCP evaluates the following comparison criteria:
File name.
User ID.
Jobname.
Device type.
Location (see next section).
Using a location specified by the user
The location of a tape is determined by the specifications in the reservation file when a reservation file is used.
A user can also specify a location in the MAREN statement RESERVE-FREE-VOLUME, in ARCHIVE, HSMS, or FDDRL. Up to and including MAREN V12.0, this specification was ignored.
In MAREN V12.5 and higher, the system-specific MAREN parameter OVERRULE-LOC decides on the further procedure:
OVERRULE-LOC=REJECT
The location specified by the user is employed (differing locations lead to the reservation being rejected).OVERRULE-LOC=YES
The location specified in the reservation file is used.