Table of Contents
Advertisement
Chapter 6 RAID Group Management
6.2 Functions in the Action Area for RAID Group
6.2.5
Expand RAID Group
This function adds drives to the existing RAID group by using the Logical Device Expansion
function to dynamically expand RAID group capacity. This function can also dynamically change
the RAID level of an existing RAID group.
RAID group expansion provides the following features without stopping the ETERNUS DX Disk
storage system operation:
•
RAID group expansion add disks to the existing RAID group in units of one drive. This
enables capacity expansion of RAID groups with smaller number of disk expansion.
•
RAID groups can be expanded and any existing data in these RAID groups is retained.
Requirements for expanding a RAID group:
•
The "Status" is "Available"
•
Standard volumes, SDVs, or SDPVs are registered
•
Not registered in the TPP
•
Not registered as a REC Disk Buffer
•
The RAID group is not blocked
•
Formatting is not being performed for the volume that is registered in the RAID group
•
Encryption is not being performed for the volume that is registered in the RAID group
•
Before expanding the RAID group, back up data in all the logical
volumes in the target RAID group to a different location. If not, data
cannot be recovered when expansion fails. If expansion fails, data can
be recovered from the backed up data.
•
When expanding drives, use drives that have the same capacity and
speed as the drives that configure the target RAID group. If drives of
different capacities exist in a RAID group, the smallest capacity
becomes the standard for the RAID group after expansion, and all other
drives are regarded as having the same capacity as the smallest drive.
In this case, the remaining drive space will NOT be used. In addition, if
drives of different speeds exist in a RAID group, the access perfor-
mance of the RAID group is reduced by the slower drives.
•
If the drives that configure the target RAID group are SSDs, SSDs must
be used when adding drives.
•
RAID groups can be expanded when the RAID group capacity after
performing expansion is the same or larger than the current RAID group
capacity.
•
The expansion of capacity can only be performed for one RAID group at
a time.
•
RAID group expansion cannot be suspended.
127
ETERNUS Web GUI User's Guide
Copyright 2011 FUJITSU LIMITED
P2X0-1090-02ENZ0
Advertisement
Table of Contents
