Selecting a RAID Level
The factors you need to consider when selecting a RAID level are listed below.
Level | Description and | Pros | Cons | Maximum | Fault |
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| Use |
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| Physical | Tolerant |
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| Drives |
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0 | Data divided in | High data | No fault | One to 32 | No |
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| blocks and | throughput | tolerance. All |
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| distributed | for large | data lost if |
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| sequentially (pure | files | any drive |
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| striping). Use for |
| fails. |
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| that requires high |
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| performance. |
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1 | Data duplicated on | 100% data | Doubles disk | Two | Yes |
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| another disk | redundancy | space. |
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| (mirroring). Use |
| Reduced |
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| for |
| performance |
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| during |
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| |
| systems |
| rebuilds. |
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3 | Disk striping with a | Achieves | Performance | Three to 32 | Yes |
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| dedicated parity | data | not as good as |
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| drive. Use for non- | redundancy | RAID 1 |
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| interactive apps | at low cost |
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| that process large |
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| files sequentially. |
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5 | Disk striping and | Achieves | Performance | Three to 32 | Yes |
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| parity data across | data | not as good as |
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| all drives. Use for | redundancy | RAID 1 |
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| high read volume | at low cost |
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| but low write |
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| volume, such as |
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| transaction |
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| processing. |
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10 | Data striping and | High data | More | Four to 32 | Yes |
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| mirrored drives. | transfers, | complicated | (must be a |
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| complete |
| multiple of |
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| redundancy |
| two) |
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30 | Disk striping with a | High data | More | Six to 32 | Yes |
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| dedicated parity | transfers, | complicated |
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| drive. | redundancy |
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50 | Disk striping and | High data | More | Six to 32 | Yes |
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| parity data across | transfers, | complicated |
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| all drives. | redundancy |
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16MegaRAID Enterprise 1600 Hardware Guide