If migration or recall is using the volume that is needed as a source volume for recycle, and the recycle request is a specific RECYCLE VOLUME(volser) request, the recycle fails. If the recycle request is a generic RECYCLE request, then the recycle of that connected set is skipped and message ARC0845I is issued to indicate such. Recycle processing continues with the next eligible connected set. If someone issues a RECYCLE command for a specific volume and that volume is the target recycle volume, DFSMShsm selects another target ML2 volume. DFSMShsm then recycles the specified volume.
Table 1 is a summary of possible volume contention in a single DFSMShsm-host environment or within the same DFSMShsm host in a multiple DFSMShsm-host environment.
| Function That Has Volume | Function That Needs Volume | Result |
|---|---|---|
| Migration | Migration | No contention. |
| Recall | Migration | Migration selects a new target volume. |
| Recycle (source) | Migration | Migration selects a new target volume. |
| Recycle (target) | Migration | No contention. |
| Migration, |
Recall | Recall initiates a tape takeaway, and periodically retries the recall. When migration or recycle processing is complete for the data set being processed, the allocated volume is released and a new volume is selected for migration or recycle processing. |
| Recall | Recall | Terminate in favor of a higher priority recall from a different tape if running at maximum tape tasks, and it has been greater than specified amount of time since tape began to be continuously mounted. |
| ABACKUP | Recall | Recall periodically retries accessing the data set on the tape. If Recall is a WAIT request, after a delay, it initiates a tape takeaway, which causes ABACKUP to skip any remaining data sets that are needed by ABACKUP on the tape and process from other migration and user tapes. ABACKUP later tries to process those data sets that were skipped earlier. |
| ARECOVER | Recall | Recalls are retried until the tape is available or a retry limit is reached. |
| TAPECOPY (source) | Recall | If tapecopy takeaway is enabled, Recall retries for 15 minutes before requesting tape takeaway. If TAPECOPY has not completed its copy within one minute of the tape takeaway request, the copy fails. |
| Migration | Recycle (source) | Recycle of this volume fails. Recycle of other eligible volumes continues. |
| Recall | Recycle (source) | Recycle of this volume fails. Recycle of other eligible volumes continues. |
| Recycle (source) | Recycle (source) | No contention. |
| Recycle (target) | Recycle (source) | Recycle selects a new target volume. |
| Migration | Recycle (target) | No contention. |
| Recall | Recycle (target) | Recycle selects a new target volume. |
| Recycle (source) | Recycle (target) | Recycle selects a new target volume. |
| Recycle (target) | Recycle (target) | Recycle selects a new target volume. |
| Migration, |
ABACKUP | ABACKUP initiates a tape takeaway and periodically retries the data set. When migration or recycle processing is complete for the data set being processed, the allocated volumes are released. A new target tape is selected for migration or recycle output contention, or a new connected set is selected if there is recycle source contention. |
| Recall | ABACKUP | ABACKUP is retried until the tape is available or a retry limit is reached. |
| ABACKUP | ABACKUP | ABACKUP skips over the tape in use and processes from other migration tapes. It reattempts to process the skipped tape later. |
| TAPECOPY (source) | All except Recall and ABACKUP | Function fails. |
| TAPECOPY (source) | ABACKUP | If tapecopy takeaway is enabled, ABACKUP retries for 15 minutes before initiating a tape takeaway. If TAPECOPY has not completed its copy within one minute of noting the takeaway request, the copy fails. |