Fujitsu ETERNUS AF250 Design Manual page 26

1. Function
RAID Functions
Type
Wide Striping Volume (WSV)
ODX Buffer volume
*1: When multiple volumes are concatenated using the LUN Concatenation function, the maximum capacity is
also 128TB.
*2: The capacity differs depending on the copy source volume capacity.
After a volume is created, formatting automatically starts. A server can access the volume while it is being for-
matted. Wait for the format to complete if high performance access is required for the volume.
In the ETERNUS AF, volumes have different stripe sizes that depend on the RAID level and the stripe depth
•
parameter.
For details about the stripe sizes for each RAID level and the stripe depth parameter values, refer to "ETER-
NUS Web GUI User's Guide".
Note that the available user capacity can be fully utilized if an exact multiple of the stripe size is set for the
volume size. If an exact multiple of the stripe size is not set for the volume size, the capacity is not fully
utilized and some areas remain unused.
When a Thin Provisioning Pool (TPP) is created, a control volume is created for each RAID group that config-
•
ures the relevant TPP. Therefore, the maximum number of volumes that can be created in the ETERNUS AF
decreases by the number of RAID groups that configure a TPP.
When the Flexible Tier function is enabled, 32 work volumes are created. The maximum number of volumes
•
that can be created in the ETERNUS AF decreases by the number of work volumes that are created.
When a Flexible Tier Sub Pool (FTSP) is created, a control volume is created for each RAID group that config-
•
ures the relevant FTSP. Therefore, the maximum number of volumes that can be created in the ETERNUS AF
decreases by the number of RAID groups that configure an FTSP.
When using the VVOL function, a single volume for the VVOL management information is created the mo-
•
ment a VVOL is created. The maximum number of volumes that can be created in the ETERNUS AF decrea-
ses by the number of volumes for the VVOL management information that are created.
Usage
This volume is created by concatenating distributed areas in
from 2 to 24 RAID groups. Processing speed is fast because
data access is distributed.
An ODX Buffer volume is a dedicated volume that is required
to use the Offloaded Data Transfer (ODX) function of Windows
Server 2012 or later. It is used to save the source data when
data is updated while a copy is being processed.
It can be created one per ETERNUS AF.
Its volume type is Standard, TPV, or FTV.
FUJITSU Storage ETERNUS AF250 S2, ETERNUS AF250 All-Flash Arrays Design Guide (Basic)
Copyright 2019 FUJITSU LIMITED
26
Maximum capacity
128TB
1TB
P3AG-1822-09ENZ0