Advantech DNS-3200 - Manual (Page 58)

DNS-3200 User’s Manual 40
Chapter 4 Managing Arrays and Disks
4.1 RAID Minimum Disk Requirements
The following table lists the minimum and maximum number of disks for
each RAID level.
4.2 Understanding Array and Disk States
The controller uses states to report the status of arrays and disks. To
ensure the health of your data, it is important to understand what each
array and disk state means as well as what causes them to change.
Array States
Within the management applications, an array is a logical device that can
exist in one of three states: NORMAL, CRITICAL, or OFFLINE. In
RAIDConsole, these states are shown in the Array List area in a column
named State. Within the bcadm program, these states also shown in the
column named State. The states are defined as follows:
Whether an array is marked as CRITICAL or OFFLINE depends on the
type of array and how many disks within the array have failed. Note the
following changes in state:
Table 4.1: Min and Max Disks for RAID levels
RAID Level Minimum Number of
Disks Maximum Number of
Disks
Volume 1 32
RAID0 2 32
RAID1 2 2
RAID1n 3 16
RAID10 4 32
RAID10n 6 32
RAID5 3 16
RAID50 6 32