IBM V7000 Introduction And Implementation Manual page 345

For example, if you have 20 x 450 GB 10 K SAS drives on one chain, one drive in these 20
drives is dedicated as a spare drive. If you have 20 x 450 GB 10 K SAS drives on both chains,
which means that there are 10 drives in each chain, then one spare drive on each chain is
created. So, if you have 40 x 450 GB 10k SAS drives on both chains, then two spare drives on
each chain are created and you have a total of 36 drives that can be array members for the
RAID setup.
global spares
Spare drives in IBM Flex System V7000 Storage Node are , which means that
any spare drive having at least the same capacity as the drive that needs to be replaced can
be used in any array. Thus, an SSD array with no SSD spare available would use an HDD
spare instead.
In our example, using the recommended configuration, the Wizard proposed to build three
arrays using the Basic RAID 5 for the 146 GB drives (discovered as 136,23GB) and one basic
RAID 5 for the 300 GB drives (discovered as 278,90 GB). If the proposed configuration meets
your requirements, click Finish, and the system automatically creates the array MDisks with a
size according to the chosen RAID level. For each of the two different drive types, a disk is
assigned as hot spare.
Storage pools are also automatically created to contain the MDisks with similar performance
characteristics, including the consideration of RAID level, number of member drives, drive
class, and so on.
After creating an array, the array MDisk members are being synchronized with each other
through a background initialization process. The progress of the initialization process can be
monitored by clicking the icon at the left of the Running Tasks status bar and then clicking
the task displayed (Figure 8-13).
Figure 8-13 Running Tasks status bar
325
Chapter 8. Storage pools