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

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

Requirements

If you are sharing SI P-VOLs with TC or UR S-VOLs, CTG pair-split has the following requirements:

• All pair operations must be performed using CCI.

• You must share SI P-VOLs with the TC or UR S-VOLs.

• The TC or UR S-VOLs that you are sharing with the SI CTG pairs must have the same status.

• If you are sharing SI volumes with UR volumes, the pair status must be the following:

• (For UR) PAIR or PSUS.

• (For SI) PAIR or COPY(PD)/COPY.

• If you are sharing SI volumes with TC volumes, the pair status must be the following:

• (For TC) PAIR or PSUS.

• (For SI) PAIR or COPY(PD)/COPY.

Restrictions

If you are sharing SI P-VOLs with TC or UR S-VOLs, CTG pair-split has the following restrictions:

• You can perform one split operation for each SI CTG.

• You can:

• Split each UR journal up to three times (equivalent to three SI CTGs).

• Quick Split or Steady Split the pairs.

For more information about the methods you can use to split pairs, see Pair splitting methods.

Guidelines

If you are sharing SI P-VOLs with TC or UR S-VOLs, use the following guidelines when performing a CTG pair-split:

• Make sure that the SI S-VOLs are in a consistent state.

For more information about maintaining consistent backups of volumes, see Maintaining consistent ShadowImage secondary volume backups.

• Ensure that all SI pairs in the CTG are in PAIR or COPY(PD)/COPY status.

 If you share SI pair P-VOLs with UR S-VOLs and you include SI pairs in a status other than PAIR or COPY(PD)/COPY in the CTG, you cannot maintain SI S-VOL consistency.