Mylex Global Array Manager, Руководство по установке и инструкция пользователя

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Configuration
Manual No. SA67-0049-01 4-43
Spanning in Global Array Manager
Spanning allows you to configure multiple drive packs or parts of multiple
drive packs as one system drive. This means that space is used from the first
array to the last identical array.
A drive pack is a group of individual disk drives (preferably identical) that
are logically tied to each other and are addressed as a single unit. In some
cases this may be called a drive “pack” when referring to just the physical
devices.
All physical devices in a drive group should be the same size; otherwise,
each of the disks in the group will have the capacity of the smallest member.
The total size of the drive group will be the size of the smallest disk in the
group multiplied by the number of disks in the group. For example, if you
have four disks of 400MB each and one disk of 200MB in a pack, the
effective capacity available for use is only 1000MB (5x200), not 1800MB.
Drive packs or groups have the following properties.
• From one to sixteen disk drives included in an individual drive pack or
group.
• The drive pack can include physical disk drives located on different
drive channels.
• The number of disk drives in a drive pack determines the possible
RAID level. To create a JBOD or RAID 0, RAID 1, RAID 3, RAID 5,
RAID 0+1 use the following table (Table 4-2):
Table 4-2. Configuring a Spanned Array
After physical disk drive packs are defined, one or more system drives may
be created from drive packs. System drives have the following properties:
RAID Level Minimum
number of
Drives
Maximum
number of
drives
Maximum
number of
drives with
Spanning
enabled
Theoretical
Maximum
number of
drives
1 2 16 112 256
2 2 2 32 32
3 3 16 112 256
4 3 16 112 256
5 3 16 112 256
0+1 1 1 16 16