NEC Storage Manager - Page 320

Appendix D Notes on Use for Data Replication
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Table D-5 Bound LD Capacity by Specification Method
Setting
Method
Specification Method How to Obtain Capacity
Capacity
Unit
Disk Count Specification
Divide the recommended maximum
capacity*2, which is within the RANK
capacity, by the number of data disks.
1MB
Capacity Specification
*1
Specified capacity 0.1GB
*3
Batch
Setting
Disk Count and Capacity Specification
*1
Specified capacity 0.1GB
*3
Disk Count Specification
Divide the RANK capacity by the number of
data disks.
1MB
Capacity Specification
*1
Specified capacity 0.1GB
*3
Individual
Setting
Disk Count and Capacity Specification
*1
Specified capacity 0.1GB
*3
*1: For “Disk Count and Capacity Specification”, Capacity has a higher priority than Disk Count.
Thus, the capacity of the bound logical disk is the same as when it is obtained by “Capacity
Specification”.
*2: Recommended capacity = 2128MB × n (n = 1, 2, 3, ...)
If the RANK capacity is 266.7GB (= 273100.8MB), the recommended capacity is 2128MB × 128 =
272384MB.
*3: A capacity must be specified in units of 0.1GB (0.1GB = 1024MB/10).
Examples 1: Binding with Capacity Specification
1. Capacity obtained when logical disks are bound with 1.1GB specified for RAID5 (4+P):
Both Batch Setting and Individual Setting can bind logical disks of the same capacity.
1.1GB × 1024 = 1126.4MB → (Decimal place rounded up) → 1127MB → (+2MB)* →
1129MB → (Alignment) → 1129MB
2. Capacity obtained when logical disks are bound with 1.1GB specified for RAID5 (3+P):
Only Individual Setting can bind logical disks in configuration of RAID5 (3+P).
1.1GB × 1024 = 1126.4MB → (Decimal place rounded up) → 1127MB → (+2MB)* →
1129MB → (Alignment) → 1131MB
*: Logical disks are bound in the user-specified capacity + 2MB as the disk array management area.
Examples 2: Binding with Disk Count Specification
1. Capacity obtained when three logical disks are bound with 266.7GB as the RANK capacity of
RAID5 (4+P): Batch Setting and Individual Setting bind the logical disks of different capacities.
(With Batch Setting)
266.7GB × 1024 = 273100.8MB > 2128MB×n → 2128MB×128 → 272384MB →
272384MB/3 = 90794.66MB → (Decimal places rounded down) → 90794MB → (Alignment)
→ 90794MB*
(With Individual Setting)
266.7GB × 1024/3 = 91033.6MB → (Decimal place rounded down) → 91033MB →
(Alignment) → 91033MB*