| Additional | 16 |
| enclosures to a | |
|
| |
Loop 0 | maximum of four |
|
per loop | 1 | |
|
|
(accessed via the disk exp ports)
| 16 |
Expansion |
|
enclosure 2 | 1 |
16
Server Enclosure
1
Device adapter chipset inside controller 1
FC switch
16 DDMs per
enclosure
2Gb
4
Device adapter chipset inside controller 2
Loop 1
(accessed via
the disk
contrl ports)
Expansion | 1 |
| |
enclosure 1 |
|
| 16 |
Expansion | 1 |
| |
enclosure 3 | 16 |
Additional |
|
enclosures to a | 1 |
maximum of four |
|
per loop | 16 |
Figure 8-7 Example of connecting several expansion enclosures
8.4.2 Logical configurations
The capacity of the physical disk drives is not equal to the capacity you can use in the DS6000 series. Among the reasons for this are that the user will configure either
The logical capacity depends on not only the capacity of the DDMs but also the RAID type and the number of spare disks in a rank. We describe the capacity in the following figures.
Attention:
The figures used in this chapter are still subject to change. Specifically, the exact number of extents per rank may be slightly different.
You might ensure there is at least 5% of additional capacity, if you are providing an exact number of devices.
–There will also potentially be unusable space for devices which are not an integer number of extents in size and for the last extent in an extent pool.
–To prepare for unexpected situations, a certain amount of margin is required for important systems.
Chapter 8. Configuration planning | 139 |
