Questions And Answers - Compaq 166207-B21 - Smart Array 5302/32 RAID Controller Reference Manual

Q: What is RAID ADG?
A: RAID ADG is an extension of RAID 5 that allows additional fault
tolerance by using two different and independent parity schemes. Data is
striped across a set of hard drives, just as with RAID 5, and the two sets of
parity data are calculated and written across all the drives in the array.
RAID ADG provides an extremely high fault tolerance, and can sustain
two simultaneous drive failures without downtime or data loss. This is a
perfect solution when data is mission-critical.
Q: What does the abbreviation RAID ADG mean?
A: ADG is an abbreviation for Advanced Data Guarding, the term Compaq
uses for this type of fault tolerance.
Q: When should RAID ADG be used?
A: There are three primary reasons for using RAID ADG.
!
When a higher level of fault tolerance than RAID 5 is needed and
high drive capacity utilization is also required
! When a higher level of drive capacity utilization than RAID 0+1 is
required while maintaining a high level of fault tolerance
!
When a large logical volume is needed, incorporating from 10 to 56
hard drives

Questions and Answers

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