Two Disk Groups (Raid 6), Zero Hot Spares - Dell NX3600 Deployment Manual

High Availability A RAID 5 disk group can continue to execute read and write requests to all its virtual disks
after a single disk failure. As long as there is enough time to rebuild between failures, with hot
spares, there can be three disk drive failures before read and write requests cannot be
executed.

Two Disk Groups (RAID 6), Zero Hot Spares

Space This option consists of two RAID 6 disk groups with a single virtual disk in each group and no
hot spares. Each RAID 6 disk group is made up of six, 2 TB hard drives. In RAID 6, the available
space in each disk group is 8 TB as two hard disks are allocated for parity. The NAS cluster
requires pairs of equal sized virtual disks. Therefore, each disk group is divided into a single 8
TB virtual disk utilizing all available space in its disk group. You have 16 TB space to be
allocated for the NAS cluster.
High Availability A RAID 6 disk group can continue to execute read and write requests to all of its virtual disks
after any two concurrent disk failures. Since the physical disks are split between two disk
groups, data can continue to be read and written if four concurrent disks fail, as long as no
more than two fail in each disk group.
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