Binding Disk Modules Into Raid Groups; Disk Configuration Rules And Recommendations - Dell DAE2-ATA Hardware Reference Manual

Binding Disk Modules into RAID Groups

Disk Configuration Rules and Recommendations

After cabling the disk enclosure, use EMC Navisphere
software to bind the disks into RAID groups. Refer to the EMC
Navisphere Manager Revision 6.X Administrator's Guide and your
storage processor configuration and planning guide for detailed
information.
The following rules and recommendations apply to all CX-Series
systems.
You cannot use disks 000 through 004 (enclosure 0, loop 0, disks
0-4) as a hot spare in a CX-Series system.
On CX-Series systems, the hardware reserves several gigabytes
on each of disks 000 through 004 for the cache vault and internal
tables. To conserve disk space, you should avoid binding any
other disk into a RAID Group that includes any of these disks.
Any disk you include in a RAID Group with a cache disk 000-004
is bound to match the lower unreserved capacity, resulting in lost
storage of several gigabytes per disk.
Each disk in the RAID Group should have the same capacity. All
disks in a Group are bound to match the smallest capacity disk,
and you could waste disk space. The first five drives (000-004)
should always be the same size.
You cannot mix ATA (Advanced Technology Attachment) and
Fibre Channel disk drives within a RAID Group.
Hot spares for Fibre Channel drives must be Fibre Channel
drives; ATA drives require ATA hot spares.
If a storage system will use disks of different speeds (for example,
10K and 15K rpm), then EMC recommends that you use disks of
the same speed throughout each 15-disk enclosure. For any
enclosure, the hardware allows one speed change within an
enclosure, so you may use disks of differing speeds. Place the
higher speed drives in the first (leftmost) drive slot(s).
You should always use disks of the same speed and capacity in
any RAID Group.
Do not use ATA drives to store boot images of an operating
system. You must boot host operating systems from a Fibre
Channel drive.

Binding Disk Modules into RAID Groups

Installing a DAE2
®
Manager
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