HP StorageWorks XP Remote Web Console Software - Manual (Page 63)

secondary storage system, one of the secondary storage systems is used to perform tasks including
arbitration processing on the other secondary storage systems.
•
The term supervisor DKC is used to identify the storage system that performs arbitration
processing.
•
The term subordinate DKCs is used to identify the storage systems that are controlled by the
supervisor DKC and are targets of arbitration processing.
The supervisor DKC performs the following function when controlling the subordinate DKCs:
Compares the time stamps of data received by all the secondary storage systems (including the
local storage system) and then performs arbitration processing.
In the example in Figure 14 (page 62) , secondary storage system 1 is the supervisor DKC, and
secondary storage systems 2 and 3 are subordinate DKCs.
To perform arbitration processing, the supervisor DKC must be connected with the subordinate
DKCs. For details on connections between secondary storage systems, see
“Connections Between
Secondary Storage Systems” (page 64) .
Basic Behavior When Using Multiple Primary and Secondary Storage Systems
This section explains the basic behavior of Universal Replicator for Mainframe under the following
conditions:
•
There are two primary storage systems and two secondary storage systems.
•
The status of all the Universal Replicator for Mainframe pairs that use journal groups in the
extended consistency group is Duplex. For details on extended consistency groups, see
“Extended Consistency Groups” (page 22) .
•
The primary host issues write requests to Universal Replicator for Mainframe primary data
volumes.
The following figure illustrates a Universal Replicator for Mainframe operation when the above
conditions are satisfied.
Figure 15 A Universal Replicator for Mainframe Operation When Two Primary Storage Systems
and Two Secondary Storage Systems are Used
The numbers in Figure 15 (page 63) indicate the order that the processing is performed, and
correspond to the numbers in this procedure:
Using Multiple Primary and Secondary Storage Systems 63