Raid Protection For Internal Disks - IBM Power System E850C Technical Overview And Introduction

2.10.2 RAID protection for internal disks

There are multiple protection options for HDD/SSD drives in the Power E850C server,
whether they are contained in the internal SFF or 1.8-inch bays in the system unit or in
disk-only I/O drawers like the EXP24S. Although protecting drives is always recommended,
AIX and Linux users can choose to leave a few or all drives unprotected at their own risk. IBM
supports these configurations.
HDD/SSD drive protection can be provided by AIX and Linux, or by the available hardware
controllers.
All three of these controller options can offer different drive protection options: RAID 0,
RAID 5, RAID 6, or RAID 10. RAID 5 requires a minimum of three drives of the same
capacity. RAID 6 requires a minimum of four drives of the same capacity. RAID 10 requires a
minimum of two drives. Hot spare capability is supported by RAID 5 or RAID 6.
All three controller options offer Easy Tier functionality, which is also called
(2-tiered RAID 5),
disk backplane option supports RAID 10T2, but does not support RAID 5T2 or 6T2.
Table 2-25 details the drive protection options that are available with each storage controller
option available with the Power E850C server.
Table 2-25 Drive protection capabilities of the Power E850C storage controller options
Protection type
JBOD
RAID 0/1
RAID 5/6/10
RAID 5T2 (Easy Tier)
RAID 6T2 (Easy Tier)
RAID 10T2 (Easy Tier)
Split backplane
56
IBM Power System E850C: Technical Overview and Introduction
RAID 6T2
(2-tiered RAID 6), and
Dual controller with
write cache (#EPVN)
No
Yes
Yes
Yes
Yes
Yes
No
RAID 10T2
(2-tiered RAID 10). The split
Dual controller without
write cache (#EPVP)
No
Yes
Yes
Yes
Yes
Yes
No
RAID 5T2
Split disk backplane
(#EPVQ)
Yes
Yes
Yes
No
No
Yes
Yes