Table of Contents

 

1 Overview ...............................................................

1

Single Ended and Differential SCSI Buses ..............................

2

Maximum Cable Length for SCSI Standards ...........................

2

Documentation .........................................................................

3

ADAC Ultra2 S466 Block Diagram.........................................

4

2 Introduction to RAID ............................................

5

RAID Benefits..........................................................................

5

In This Chapter.........................................................................

6

ADAC Ultra2 S466 – Host-Based RAID Solution...................

7

RAID Overview .......................................................................

8

Consistency Check ...................................................................

8

Fault Tolerance ........................................................................

8

Disk Striping ............................................................................

9

Disk Spanning ........................................................................

10

Disk Mirroring .......................................................................

11

Parity ......................................................................................

12

Hot Spares ..............................................................................

13

Disk Rebuild...........................................................................

14

Logical Drive .........................................................................

15

Hot Swap................................................................................

15

SCSI Drive States...................................................................

16

Logical Drive States ...............................................................

16

Disk Array Types ...................................................................

17

Enclosure Management ..........................................................

17

3 RAID Levels ........................................................

19

Selecting a RAID Level .........................................................

20

RAID 0 ...................................................................................

21

RAID 1 ...................................................................................

22

RAID 3 ...................................................................................

23

RAID 5 ...................................................................................

25

RAID 10 .................................................................................

26

RAID 30 .................................................................................

27

RAID 50 .................................................................................

28

4 ADAC Ultra2 S466 Features ..............................

29

Hardware Requirements .........................................................

30

Configuration Features ...........................................................

30

Hardware Architecture Features.............................................

31

Array Performance Features...................................................

31

RAID Management Features ..................................................

32

Fault Tolerance Features ........................................................

32

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