Sun Cluster Geographic Edition Data Replication Guide for Hitachi TrueCopy

Determining the Aggregate Hitachi TrueCopy Device Group State

If a protection group contains only one Hitachi TrueCopy device group, then the aggregate device group state is the same as the individual device group state.

When a protection group contains multiple Hitachi TrueCopy device groups, the aggregate device group state is obtained as described in the following table.

Table 2–2 Conditions That Determine the Aggregate Device Group State

Condition 

Aggregate Device Group State 

All individual device group states are SMPL

SMPL

All individual device group states are either Regular Primary or SMPL

Regular Primary

All individual device group states are either Regular Secondary or SMPL

Regular Secondary

All individual device group states are either Takeover Primary or SMPL

Takeover Primary

All individual device group states are either Takeover Secondary or SMPL

Takeover Secondary

The aggregate device group state cannot be obtained for any other combination of individual device group states. This is considered a pair-state validation failure.