Assigning TC and TCz pairs to the same consistency group

TrueCopy pairs can be in the same consistency group as TrueCopy for Mainframe pairs. Use the same consistency group ID for both types. Determine the consistency group ID by using CCI or Business Continuity Manager in advance. Use an unused consistency group ID.

Before defining pairs in CCI, specify the consistency group ID. In Business Continuity Manager, use the Copy Group Attributes (TC) window to set the consistency group ID, and then define pairs. For details about the Copy Group Attributes (TC) window, see the Business Continuity Manager User Guide.

When performing a split operation for each group through CCI or Business Continuity Manager, TrueCopy pairs and TrueCopy for Mainframe pairs assigned in the same consistency group are split, and then the data of TrueCopy pairs and TrueCopy for Mainframe pairs is guaranteed until the time that the split operations are accepted. At that time, the YKFREEZE and YKRUN are not required.

When write I/Os are received in the P-VOL of the TrueCopy pairs or the TrueCopy for Mainframe pairs in the target consistency group during the processing of step 2 through step 5, if the volume pair in which I/Os are received is not split, split the pair, and then perform the write I/O operations.

The data consistency is ensured by differentiating data instead of copying data in the S-VOL because the pairs have been split during the write I/O operations.

The following figure shows the pair split processing for each group when TrueCopy pairs #1 and #2, and TrueCopy pairs #3 and #4 are assigned to the same consistency group.

The following is the procedure for pair split processing for each group when TrueCopy and TrueCopy for Mainframe pairs are assigned in the same consistency group.