Choosing the Right Disk Technology in a High Availability Environment DRAFT Version 2.0, August 1996

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DRAFT -- Revision 2.0
August 22, 1996Page 26
Figure 6: High Availability Configuration using the AutoRAID Disk Array and
PVLinks
Advantages and Disadvantages of AutoRAID Disk Arrays
+ smaller overall footprint for a given amount of storage
+ lower cost for moderate to large configurations
+ easy on-line replacement of failed disk mechanisms
+ hot standby is active and automatically assigned
+ highest storage connectivity since each array uses only 2 SCSI target
addresses
+ flexibility of configuration
administrator chooses the amount of space allocated to RAID 1 mode
automatic and dynamic migration of data between RAID 5 and RAID 0/1
according to the application’s data access patterns
+ potential for high performance with no a priori knowledge of application data
access patterns and no need for data placement (especially for write-intensive
applications)
+ no SPOFs when used with two separate power sources