CA VM:Backup passes three arguments to VMBEXIT1. The first provides tape information about drive allocation and tape owner, the second lists the volsers of the tapes to be mounted, and the third provides the tape data set name.
Argument 1:
vaddr numvol medium densityname mode expdt retpd owner
Argument 2:
vol1 <vol2 <vol3 <vol4 <vol5>>>>
Argument 3:
dataset
Specifies the virtual address of the drive used to attach the tape.
Specifies the number of tapes identified in the second argument. Backups can specify only one tape. Restores can specify a maximum of five to make up to four copies (plus the primary) available.
Specifies the media type and density of the tape. For more information about media types and density names, see Tape Drives, Media, Density Names, and TMC Values.
Specifies whether CA VM:Backup should attach the tape in read/write or read-only mode. Tapes for backups, MPC, and REINIT jobs must be attached read/write, and tapes for restores must be attached read-only.
Specifies the tape expiration date in yyyy/ddd format for backup tapes and output tapes used in MPC jobs. If the tape expiration date is PERM, indicating that the tape should not expire in the tape management system, CA VM:Backup passes PERM for this parameter.
Specifies the number of days CA VM:Backup should retain the tape before expiring it for backup jobs and output tape used in MPC jobs. If the tape expiration date is PERM, indicating that the tape should not expire in the tape management system, CA VM:Backup passes PERM for this parameter.
Specifies the user ID that will own the tape in the tape management system. Owner is specified only for backup and MPC jobs.
Specifies the tapes being mounted. When more than one volser is specified for a restore, all have the same medium and density.
Specifies the data set name written to the tape during the backup or MPC job. The data set name is usually based on the tape copy number, such as VMBACKUP.PRIMARY or VMBACKUP.COPY1. This argument, which is only meaningful for backup tapes and MPC output tapes, contains blanks when the user exit is used for tapes for restores, MPC input tapes, and tapes used for REINIT jobs.
The user exit must pass back a return code in fullword format (a four-byte hexadecimal value) or in whole number format. From REXX, this can be done with the following:
return d2c(rcode,4)
return code
Nonzero return codes indicate that the mount has failed, while a return code of zero indicates that the tape mount process completed successfully.
When control is returned from the user exit, CA VM:Backup checks every seven seconds to see whether the requested device has been attached. When the drive is attached, CA VM:Backup assumes the tape has been mounted. If the tape is not mounted, VMBEXIT1 is called again; this may result in a loop condition. CA VM:Backup immediately starts reading the tape labels to continue the job.
If the wait time specified for tape operators in the VMBACKUP CONFIG file expires before the drive is attached, the VMBEXIT1 mount request fails and the job is put on hold. The CA VM:Backup system administrator can interactively set the TAPEWAIT limit by using the Manage Configuration Options screen.
Detaching Tape Drives
If you require the tape drive to be detached before calling the user exit, make sure the VMBACKUP CONFIG file specifies that CA VM:Backup is to unload tapes and detach the tape drive as it processes each tape used in the job. The CA VM:Backup system administrator can interactively set the DETACH option of the TAPEDISP record by using the Manage Configuration Options screen.
Using Tape Copies
As a performance consideration, VMBEXIT1 should not be used with more than one tape copy because only one tape mount request can be processed at a time. VMBEXIT1 is called sequentially for each mount to prevent overlap in the mounting of tapes. Using tape copies greatly increases processing time.
|
Copyright © 2014 CA Technologies.
All rights reserved.
|
|