Fujitsu Figure E.1 Basic size when creating volumes

Appendix E Basic Size and MWC Input Condition for RAID Groups
E.1 Basic Size for each RAID Group
ETERNUS Web GUI User’s Guide
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*1: D: Data, M: Mirror, P: Parity
*2: Basic size when creating volumes.
ETERNUS DX80 S2/DX90 S2, ETERNUS DX410 S2/DX440 S2, and ETERNUS DX8100 S2/DX8700 S2 manages volumes in
units of stripe size. If the volume size is not an exact multiple of the basic size (stripe size), then when a RAID group
is created the remainder at the end of the last stripe used will be lost. Stripe size is independent of the disk drive
capacity. Figure E.1 shows what happens when the volume size is an integral multiple of the basic size and what
happens when it is not.
Figure E.1 Basic size when creating volumes
Unusable area
Unusable area
RAID Group B
Volume 1
Volume 2
Basic size
RAID group A
Volume 1
Volume 2
Basic size
Volume size is the exact multiple of basic size Volume size is not the exact multiple of basic size
Next volume is created from the next boundary Next volume is created from the next boundary
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