NEC BladeServer Express5800 Series User Manual page 90

Striping of RAID1
Data to be recorded is distributed to two HDDs in mirroring mode. Then, each mirrored data is
written onto HDD by striping. Owing to this feature, high disk access performance of RAID0 and,
in addition, high reliability of RAID1 can be achieved.
HDD 1
Stripe 1
Stripe 3
Stripe 5
Striping of RAID5
Data is distributed to HDDs by striping with distributed parity, and then written onto HDDs by
striping. Owing to this feature, high disk access performance of RAID0 and, in addition, high
reliability of RAID5 can be achieved.
HDD 1
Stripe 1
Stripe 6
Parity (9, 10)
Disk array controller
HDD 2
Stripe 1
Stripe 3
Stripe 5
RAID1
HDD 2 HDD 3
Stripe 2 Parity (1, 2)
Parity (5, 6) Stripe 5
Stripe 9 Stripe 10
RAID5
HDD 3
Stripe 2
Stripe 4
Stripe 6
RAID0
Disk array controller
HDD 4
Stripe 3
Stripe 8
Parity (11, 12)
RAID0
Configuring Your Server 4-33
HDD 4
Stripe 2
Stripe 4
Stripe 6
RAID1
HDD 5
Stripe 4
Parity (7, 8)
Stripe 11
RAID5
HDD 6
Parity (3, 4)
Stripe 7
Stripe 12