VCC Scan and GDPS

Products

• MICS Resource Management

Issue/Introduction

What are the implications of running VCC Scan with GDPS environments?

Resolution

During VCC processing:

All UCBs are pinned so that any dynamically added devices are not deleted during VCC execution. Once processing of the UCB is completed the UCB is unpinned.

VCC doesn’t detect the ACTIVATE process of the GDPS HyperSwap.
Therefore, the following message might occur if ACTIVATE request and VCC scan happen at the same time:
-
REASON=0151,CAN NOT DELETE DEVICE nnnn
   DESCTEXT=DEVICE PINNED, ASID = xxxx    
-
See the IBM IOS500I Message Documentation:

reason

A message that explains why the device was pinned.

System action: The system rejects the ACTIVATE request.

Operator response: Enter the ACTIVATE request again. If the problem occurs again, notify the system programmer.

System programmer response: If the device was pinned because an error occurred, try to unpin the device. If you cannot unpin the device, modify the target IODF so the device is not deleted. Enter the ACTIVATE request again.
...

Possible circumventions:

1.    Run VCC scan and GDPS HyperSwap activation at different times. The VCC must not run concurrently with a GDPS HyperSwap ACTIVATE operation and no ACTIVATE is scheduled during the VCC processing.
2.    (Not recommended) Exclude devices from VCC processing using corresponding VCC Runtime Parameters, for example, EXCLUDEDEV, EXCLUDEDV4.
        This option is not recommended because the VCC/VCA reports will be without information about the excluded devices.

        EXCLUDEDEV/INCLUDEDEV (standard)

        Specifies three-digit device addresses that are not eligible or that are eligible for processing by VCC. Specify INCLUDEDEV or EXCLUDEDEV as a list of device addresses.
        Up to 2000 device addresses might be included in the list.  You can reduce the amount of keying involved by using generic specifications.
        Only one of the following parameters might be used for a VCC scan: INCLUDEDEV, EXCLUDEDEV, INCLUDEDV4, or EXCLUDEDV4.
        By default VCC scans all DASD volumes that are online, resident, and ready.
        If you also code the INCLUDEVOL/EXCLUDEVOL parameter, both the volume serial number and device address tests must be met or VCC will not select the volume.

        Example: EXCLUDEDEV=(480,3B1,8FF,52*,54*,900)