Additional information on pair status

• When a pair is split by the user or suspended by the system, the primary storage system notifies the hosts by issuing a service information message (SIM). If SNMP is installed and operational, this SIM results in an SNMP trap indicating the reason for suspension.

• Transitional states occur when a request is accepted to change the pair status to PSUS, PSUE, or to delete the pair, but the operation is not yet complete. Transitional states are not reported to the host.

• The user or the primary or secondary storage system can initiate the PSUS/PSUE status change.

• Only the user can delete a pair.

• When you perform an operation, the system reports the final status at the end of the operation.

• If an error causes the status to change to PSUE, the status is reported at the beginning of the transition.

• A pair in Flush mode (remaining primary update data is flushing to the secondary storage system) remains in Suspending or Deleting status until the data in the master and restore journals is the same and the pair is completely split or released. To calculate the time during which the pair remains in the Suspending or Deleting status, use the following equation:

C × (u / 100) × 1,024 / V (The unit is seconds)

where:

• C is the total capacity (GB) of the master journal volume.

• u is the usage rate of data (%) in the master journal volume.

• V is the data transfer speed (MB/sec) between the primary and the secondary storage systems.