
262 4.5 Leveraging storage technologies
recovery within 8 hours for complete site destruction, 20mn for sim-
ple site failover—1 day of information loss maximum
No downtime (99.999 percent availability)
No more than 4 hours downtime, once a month (99.7 percent
availability)
Other Approaches: log shipping and out-of-band replication,
storage virtualization
The principle of replication is to transport data to a remote site and keep it
in sync, as much as possible, with the “live” production copy. There are
other principles that are present in other database environments, which
could eventually be found in future releases of Microsoft Exchange.
The ...