VERITAS FlashSnap Point-In-Time-Copy Solutions Administrator's Guide

Chapter 1, Point-In-Time Copy Solutions
Implementing Point-In Time Copy Solutions on a Primary Host
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The figure, “Example Point-In-Time Copy Solution on a Primary Host” on page 11, shows the
suggested arrangement for implementing solutions where the primary host is used and disk
contention is to be avoided.
Example Point-In-Time Copy Solution on a Primary Host
In this setup, it is recommended that separate paths (shown as 1 and 2) from separate controllers be
configured to the disks containing the primary volumes and the snapshot volumes. This avoids
contention for disk access, but the primary host’s CPU, memory and I/O resources are more heavily
utilized when the processing application is run.
Note For space-optimized or unsynchronized full-sized instant snapshots, it is not possible to
isolate the I/O pathways in this way. This is because such snapshots only contain the
contents of changed regions from the original volume. If applications access data that
remains in unchanged regions, this is read from the original volume.
Disks containing primary
volumes used to hold
production databases or file
systems
Disks containing
synchronized full-sized
instant snapshot volumes
Primary Host
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SCSI or Fibre
Channel Connectivity