Requirements, restrictions, and guidelines for using consistency group pair-split with shared volumes

ShadowImage for Mainframe User Guide for VSP One Block 85

Version
10.5.x
Audience
anonymous
Part Number
MK-26VSP1B035-02
ft:lastEdition
2026-05-04

You can share SIz P-VOLs with TCz or URz S-VOLs but there are requirements, restrictions, and guidelines for using consistency group (CTG) pair-split in these cases.

Requirements

If you are sharing SIz P-VOLs with TCz or URz S-VOLs, CTG pair-split has the following requirements:

  • All pair operations must be performed using CCI, Business Continuity Manager (BCM), or IBM® PPRC. The examples in this document assume you are using BCM.
  • (VSP One Block 85) To perform a CTG pair-split on ShadowImage pairs, pair operations must be done using CCI.
  • You must share SIz P-VOLs with the TCz or URz S-VOLs.
  • The TCz or URz S-VOLs that you are sharing with the SIz CTG pairs must have the same status.
  • If you are sharing SIz P-VOLs with URz volumes or TCz volumes, the pair status must be as shown in the following table.

    Volume shared with SIz P-VOLs

    Pair status of the shared volumes

    Can CTG pair-split be performed?

    URz S-VOLs

    COPY

    No

    PAIR

    Yes

    PSUS

    Yes

    PSUE (VSP One B85 only)

    Yes

    TCz S-VOLs

    COPY

    No

    PAIR

    Yes

    PSUS

    Yes

    PSUE (VSP One B85 only)

    Yes

Restrictions

Consistency group (CTG) pair-split has the following restrictions:

  • To perform a CTG pair-split on ShadowImage for Mainframe pairs, the pairs must have been created using BCM, IBM® PPRC, or CCI.
  • To perform a CTG pair-split more than once, the status of all pairs in the CTG must have changed to the status specified by the BCM YKEWAIT command.

Guidelines

If you are sharing SIz P-VOLs with TCz or URz S-VOLs, use the following guidelines when performing a CTG pair-split:

  • Make sure that the SIz S-VOLs are in a consistent state.
  • Ensure that all SIz pairs in the CTG are in PAIR/DUPLEX or CPPD/PENDING status.
    Note: If you share SIz pair P-VOLs with URz S-VOLs and you include SIz pairs in a status other than PAIR/DUPLEX or CPPD/PENDING in the CTG, you cannot maintain SIz S-VOL consistency.
  • When an ESE-VOL is used as a BCM P-VOL, initializing data by the DFSMSdss SPACEREL or ICKDSF INIT command for releasing pages in the DP pool does not work with the ATTIME Suspend function. In this case, the pages might not be released even though you run the command. If this occurs, retry running the DFSMSdss SPACEREL/ICKDSF INIT command after the pair status is changed to PSUS(or SSUS)/SUSPOP.