You determine which storage system pairs to include in each consistency group based on business criteria for keeping the status consistent across a group of up to four pairs, and for performing specific operations at the same time on all pairs in the group.
Consistency groups allow you to perform one operation on all pairs in the group at the same time. Consistency groups also ensure that all pairs are managed in a consistent status.
A consistency group has the following characteristics:
- A maximum of four storage system pairings can be placed in one consistency group.
- A consistency group can consist of the following:
- TC pairs only using one primary and one secondary storage system
- TC pairs only using more than one primary and secondary storage system
- TCz pairs only using one primary and one secondary storage system
- TCz pairs only using more than one primary and secondary storage system
- Both TC and TCz pairs using one primary and one secondary storage system
- Both TC and TCz pairs using more than one primary and secondary storage system
Note: If you connect with VSP One Block, the CTG ID for the P-VOL and S-VOL in a pair must be the same. The range of values for the ID is as follows:
When connecting to VSP E590, VSP E790,VSP G350, VSP G370, VSP G700, VSP F350, VSP F370, VSP F700: 0 to 127