HP StorageWorks XP Remote Web Console Software - Manual (Page 34)

NOTE:
Two or more initiator ports must be configured before you can add the secondary storage systems and
create the URz volume pairs.
The fibre-channel interface ports that are assigned for the RCU target ports can be connected to the
host channel paths via the fibre-channel switch.
See
Configuring Port Attributes on page 112Configuring Port Attributes for the information on configuring
host interface port.
Remote Copy Operations
Figure 4 on page 30 illustrates the two types of URz remote copy operations: initial copy and update
copy.
Primary host
Obtaining updated
journal data
Update copy
Write instruction
Secondary host
Initial copy
Obtaining base-journal
Primary storage system Secondary storage system
Restore
Secondary
data
volume
Restore
journal
volume
Primary
data
volume
Master
journal
volume
Figure 5 Remote Copy Operations
This section describes the following topics that are related to remote copy operations with URz:
• Initial copy operation (see the next section)
• Update copy operation
• Read and write I/O operations for URz volumes
• Secondary data volume write option
• Secondary data volume read option
• Difference management
Initial Copy Operations
Initial copy operations synchronize data in the primary data volume and data in the secondary data
volume. Initial copy operations are performed independently from host I/Os. Initial copy operations
are performed when you create a data volume pair or when you resynchronize a suspended pair. The
initial copy operation copies the base-journal data that is obtained from the primary data volume at
the primary storage system to the secondary storage system, and then restores the base-journal to the
secondary data volume.
34 Overview of Universal Replicator Operations