AOC-USAS-L8i Add-on Card User’s Manual
7-4
The BIOS-based configuration utility enables you to create IM and IME volumes during
initial setup and to reconfigure them in response to hardware failures or changes in the
environment.
7-4 Integrated RAID Firmware
This section describes features of the Integrated RAID firmware.

Resynchronization with Concurrent Host I/O Operation

The Integrated RAID firmware allows host I/Os to continue on an IM or IME volume
while the volume is being re-synchronized in the background. Resynchronization is
attempted after a hot spare is activated due to a physical device failure, or after a hot
swap has occurred to a physical disk in the volume.

Metadata Supp ort

The firmware supports metadata, which describes the IM/IME logical drive configuration
stored on each member disk. When the firmware is initialized, each member disk is
queried to read the stored metadata in order to verify the configuration. The usable disk
space for each member disk is adjusted down when the configuration is created, in
order to leave room for this data.

Hot Swapping

The firmware supports hot swapping. The hot-swapped disk is automatically
resynchronized in the background, without any host or user intervention. The firmware
detects hot swap removal and disk insertion.
Figure 7-3. Integrated Mirroring Enhanced with Three Disks
Logical View Physical View

+ +

Mirrored Stripe N
. . .
Mirrored Stripe 6
Mirrored Stripe 5
Mirrored Stripe 4
Mirrored Stripe 3
Mirrored Stripe 2
Mirrored Stripe 1
Mirrored Stripe n
Mirrored Stripe n-2
. . .
Mirrored Stripe 6
Mirrored Stripe 4
Mirrored Stripe 3
Mirrored Stripe 1
Mirrored Stripe (n-2)
Mirrored Stripe n-1
. . .
Mirrored Stripe 4
Mirrored Stripe 5
Mirrored Stripe 1
Mirrored Stripe 2
Mirrored Stripe (n-1)
Mirrored Stripe n
. . .
Mirrored Stripe 5
Mirrored Stripe 6
Mirrored Stripe 2
Mirrored Stripe 3