HP SAN Virtualization Services Platform - Manual (Page 65)

The async mirror is enabled by Point-in-Time copies of the source virtual disk and PiTs of the destination
virtual disk too.
Sync mirror
In synchronous mirroring, the host will see one virtual disk, however, every write command goes to
all mirror copies. The host application receives a response to a write command only after the write
data is successfully made to all copies.
This is very useful for the creation of high availability configurations that demand access without
failure. Service Guard would benefit from the use of synchronously mirrored data for failover situations.
To create a sync mirror for a virtual disk:
HP StorageWorks SAN Virtualization Services Platform 3.0 Virtualization Services Manager Demo
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